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COPYRIGHT DEPOSIT. 



RUBBERHAND STAMPS 

AND THE 

MANIPULATION OF RUBBER 



A PRACTICAL TREATISE ON THE MANUFACTURE OF 

INDIA RUBBER HAND STAMPS, SMAW, ARTICLES 

OF INDIA RUBBER, THE USE OF RUBBER IN 

SURGERY AND DENTISTRY, RUBBER TIRES, 

THE HEKTOGRAPH, SPECIAL INKS, 

CEMENTS AND ALUED SUBJECTS 

ALSO 

Giving the Sources of India Rubber and Its History— Its 
Collection— Properties of Unvulcanized and Vulcanized 
Rubber— The Manufacture of Masticated Mixed Sheet, 
and Vulcanized India Rubber— Various Vulcanizing 
and Curing Processes— The Solution of India Rub- 
ber — Ebonite — Vulcanite — Gutta Percha, Etc. 

BY 

T. O'CONOR SLOANE, A.M., E.M., Ph.D. 

Author of "Arithmetic of Electricity," "Electricity Simplified, 
"Standard Electrical Dictionary," etc. 




REVISED THIRD EDITION FULXY HJ.USTRATED 









NEW YORK 






THE 


NORMAN 


W. 


HENLEY 


PUBLISHING 


CO. 






132 


Nassau Street 










1912 










Copyright, 1890, by 

NORMAN W. HENI.EY & CO. 

Copyright, 1912, by 

THE NORMAN W. HENLEY PUBLISHING CO. 



U 



^m 



£C!.A316115 



*i 



\JV. 




PREFACE. 



The present work hardly needs a preface. The 
object is to present in the simplest form the subject 
of the manipulation of india rubber. To mould 
and cure the mixed gum but few appliances are 
needed, and these can be made at home. The arti- 
cles produced are of more than ordinary utility. 
These two facts give value to the art and furnish a 
raison d'etre for this book. If its instructions do 
not prove practical it will have missed its object. 

For some reason the methods of moulding the 
material are not generally known. Experiment has 
taught many the futility of attempting to melt and 
cast it. While thus intractable by the usual meth- 
ods, it is the most plastic of materials when prop- 
erly treated. Its power of reproducing the finest 
details of a mould, of entering all the intricacies 
and undercuttings of a design, cause one to feel a 
peculiar pleasure in working with so responsive a 
material. It is not saying too much to affirm that 
to some readers this book will disclose a long hidden 
secret. To make it more generally useful it is writ- 



iv PREFACE. 

ten for such readers, to meet the want of those 
knowing of the subject. It was felt that in follow- 
ing this course, and in treating the subject from its 
first steps, including the simplest as well as most 
advanced methods, the book would appeal to a 
larger body of readers. 

The allied subjects to which some chapters are 
devoted will be acceptable to many readers. The 
hektograph is given in several modifications. A 
substitute for rubber stamps which stands the 
severe usage of the Post Office has very distinct 
merits, and the manufacture is accordingly 
described in detail. Cements and inks embody 
many special formulae. In the last chapter inter- 
esting and practical notes will be found. 

For the use of certain cuts we are under obliga- 
tions to the Buffalo Dental Manufacturing Co., 
Messrs. E. & F. N. Spon & Co., and to Mr. L. Spang- 
enberg. 



Preface to Third Revised Edition 

This work has been revised and enlarged by the 
addition of chapters on the Use of Rubber in Sur- 
gery and Dentistry and the Construction and Re- 
pairing of Rubber Tires. The addition of this 
matter, we believe, will greatly interest the reader. 

June, 1912. 



CONTENTS. 



CHAPTER 1. 

THE SOURCES OF INDIA KUBBER AND ITS HISTORY. 

The Trees — The Sap — Caoutchouc — Early Uses by 
the Indians — First knowledge of it in Europe — Good- 
year, Day, and Mackintosh 

CHAPTER II. 

THE NATURAL HISTORY AND COLLECTION OF INDIA 

RUBBER. 

African, East Indian, Central and South American 
Gums — Different Methods of Collection and Coagula- 
tion 15 

CHAPTER III. 

PROPERTIES OF UNVULCANIZED AND VULCANIZED IN- 
DIA RUBBER. 

Properties of Unvulcanized Rubber; its Cohesion and 
importance of this property — Analysis of Sap and 
Caoutchouc — Effects of Heat and Cold — Distillation 
Products — Vulcanized Rubber, and its Properties 24 

CHAPTER IV. 

THE MANUFACTURE OF MASTICATED, MIXED SHEET 
AND VULCANIZED INDIA KUBBER. 

Treatment by the Manufacturer — Washing and Sheet- 



vi CONTENTS. 

ing — Masticating — Making Sheeting and Threads — Mix- 
ing — Curing — Coated Tissues 35 

CHAPTER V. 

INDIA RUBBER STAMP MAKING. 

Mixed Sheet — Outlines of Moulding — Home-Made 
Vulcanizing Press — Further Simplifications of Same — 
Securing Accurate Parallelism of Platen and Bed — Dis- 
tance Pieces — Wood vs. Iron as Material for Press — 
Use of Springs on the Home-Made Press — Metal Flask 
Clamps — Large Gas-Heated Vulcanizing Press — Prepar- 
ing Type Model — The Matrix — Plaster of Paris and 
Dental Plaster as Substances for Matrices — Dextrine 
and Gum Arabic Solutions for Mixing Matrix — How 
Matrix is made — Shellac Solution for Matrix — Matrix 
Press and Spring-Chase — How to retard the Setting of 
Plaster of Paris — Oxychloride of Zinc Matrices — Talc 
Powder — Moulding and Curing the Stamp — Kerosene 
Heating Stove — Manipulation of Press — Degree of Heat 
— Simple Test of Curing — Time Required — Combined 
Matrix Making and Vulcanizing Apparatus — Chamber 
Vulcanizers — Object of Steam in Vulcanizers — Temper- 
ature Corresponding to Different Steam Pressures — 
Jacketed Vulcanizers — Gas Regulator — Flower Pot 
Vulcanizer — Fish Kettle Vulcanizer — Making Stamps 
without any Apparatus Whatever — Notes on Type, 
Quadrats and Spaces — Autograph Stamps 47 

CHAPTER VI. 

INDIA RUBBER TYPE MAKING. 

Movable Type Making — Simple Flask and Matrix — 
Precautions as to Quantity of Rubber — Moulding — 
Curing — Cutting Type Apart — Special Steel Moulds — 
Wooden Bodied Type ... 73 



CONTENTS. vii 

CHAPTER VII. 

THE MAKING OF STAMPS AND TYPE FROM VULCAN- 
IZED INDIA RUBBER. 

Eeady Vulcanized Gum as Material for Stamps — 
Simplicity of the Process of Using It — Advantages 
and Disadvantages — Availability for Type 77 

CHAPTER VIII. 

VARIOUS TYPE MATRICES FOR RUBBER STAMPS AND 

TYPES. 

Electrotype Matrices — Papier Mache — Plong Paste — 
Flong Matrices — Beating into Model — Drying and Bak- 
ing — Struck-up Matrices — Chalk Plates 80 

CHAPTER IX. 

THE MAKING OF VARIOUS SMALL ARTICLES OF INDIA 

RUBBER. 

Suction Discs — Pencil Tips — Cane and Chair Leg 
Tips — Corks — Mats — Cord and Tubes — Bulbs and Hol- 
low Toys ...... o 85 

CHAPTER X. 

THE MANIPULATION OF SHEET RUBBER GOODS. 

Sheet Rubber Articles — Toy Balloons — Uses of Sheet 
Rubber in the Laboratory 94 

CHAPTER XI. 

VARIOUS VULCANIZING AND CURING PROCESSES. 

Liquid Curing Baths — Sulphur Bath — Haloids and 
Nitric Acid as Vulcanizers — Alkaline Sulphides — Sul- 
phur Absorption Process — Parke's Process 97 

CHAPTER XII. 

THE SOLUTION OF INDIA RUBBER. 

Mastication with Solvent — Peculiarities of the Pro- 



viii CONTENTS. 

cess — Different Solvents and their Properties — Par- 
affin — Vulcanized Rubber Solution — Aqueous Solu- 
tion 103 

CHAPTER XIII. 

EBONITE, VULCANITE AND GUTTA PERCHA. 

Ebonite and Vulcanite — Manufacture — Manipula- 
tion — Gutta Percha and its Manipulation 108 

CHAPTER XIV. 

GLUE OR COMPOSITION STAMPS. 

Substitute for Rubber Stamps — The United States 
Government Formula — Models and Moulds — Dating 
— Handles 113 

CHAPTER XV. 

RUBBER IN SURGERY AND DENTISTRY. 

Rubber in Surgery and Dentistry 121 

CHAPTER XVI. 

RUBBER TIRES. 

Constructing and Repairing Rubber Vehicle Tires — 
Rubber Preparations — Chemical or Cold Vulcanizing 127 

CHAPTER XVII. 

THE HEKTOGRAPH. 

How Made — The French Government Formula — 
Hektograph Sheets 142 

CHAPTER XVIII. 

CEMENTS. 

Marine Glue, and other special Cements 1 46 

CHAPTER XIX. 

INKS. 

Hektograph, Stencil and Marking Inks — White and 
Metallic Inks 150 

CHAPTER XX. 

MISCELLANEOUS. 

Preservation and Renovation of India Rubber — 
Burned Rubber for Artists — India Rubber Substitutes 
— General Notes of Interest 155 



RUBBER HAND STAMP MAKING 

AND THE MANIPULATION 

OF RUBBER. 



CHAPTER I. 

THE SOURCES OF INDIA RUBBER AND ITS HISTORY. 

India rubber or caoutchouc is a very peculiar 
product, which is found in and extracted from the 
juice of certain trees and shrubs. These are quite 
numerous and are referred for the most part to the 
following families: Euphorbiacesed, Urticaceaed, Ar- 
tocarpeaad, Asclepiadaceaed, and (Jinchonacea?d. It 
is evident that a considerable number of trees are 
utilized in commerce for its production, and it is 
certain that it exists, quite widely distributed, in 
many cases as a constituent of the juice of plants 
not recognized as containing it. 

When an india rubber tree is tapped, which is 
effected by making incisions in the bark, the sap of 
the tree exudes. It is a milky substance and is 
collected in various ways; it may be in vessels of 



10 RUBBER HAND STAMP MAKING 

clay, in shells, or in other receptacles by the india 
rubber hunters. If this substance is examined it is 
found to be of very remarkable and characteristic 
constitution, resembling in its physical features 
ordinary milk. It is composed of from fifty to 
ninety per cent, of water, in which is suspended in 
microscopic globules, like the cream in milk, the 
desired caoutchouc or india rubber. If the juice is 
left to stand in vessels, like milk in a creamery, the 
globules rise to the surface, and a cream of india 
rubber can be skimmed off from the surface. If 
the juice is evaporated over a fire, the water escapes 
and the india rubber remains. By dipping an 
article repeatedly in the juice and drying it, a thick 
or thin coating of india rubber can be developed. 
Before the modern methods for the manipulation of 
the gum had been developed, and before the inven- 
tion of vulcanization, this method was adopted for 
the manufacture of shoes. The original " india 
rubbers " for protection of the feet in wet weather 
were made in this manner. A clay last was used, 
upon which the india rubber was deposited as 
described. The clay last was then broken out and 
removed. Great quantities of overshoes were thus 
made in South America, and many were exported to 
Europe. 

When caoutchouc has once been removed from 
this watery emulsion, which for all practical pur- 
poses is a solution, it cannot be restored to the 
former state of liquidity; it remains solid. It will 



AND THE MANIPULATION OF RUBBER. 11 

absorb a considerable quantity of water, but will 
not enter again into the quasi solution or combina- 
tion. This property of permanent coagulation, 
which interferes to a degree with its easy manipula- 
tion, was early discovered. In the last century 
quantities of the natural milk were exported to 
Europe to be used in what may be termed the nat- 
ural process of manufacture, because once solidified 
it could not be redissolved, and because the manu- 
facturers of those days had not the present methods 
of dealing with the apparently intractable gum. 

The natives of South America before the advent 
of Europeans, were familiar with the treatment of 
the juice by evaporation just described and used to 
make bottles, shoes and syringes of it for their own 
use. The name Siphonia applied to several species 
of rubber tree, and seringa (caoutchouc) and 
seringari (caoutchouc gatherer) in Spanish recall 
the old Indian syringes and tubes. 

The gum is now collected for export in many 
parts of the world. South and Central America 
are, as they have always been, the greatest produ- 
cers. Some is collected in Africa, Java and India. 
The best comes from Para. However carefully 
treated a great difference is found in the product 
from different countries. The Brazilian india rub- 
ber, known as Para, from the port of shipment, 
ranks as the best in the market. 

Its history as far as recorded, does not go back of 
the last century. Le Oondamine, who explored the 



12 RUBBER HAND STAMP MAKING 

Amazon River, sent from South America in 1736 to 
the Institute de France, in Paris, the first sample of 
india rubber ever seen in Europe. He accompanied 
the sample with a communication. He said that 
the Indians of that country used the gum in making 
several domestic objects of utility, such as vessels, 
bottles, boots, waterproof clothing, etc. He stated 
that it was attacked and to a certain extent dis- 
solved by warm nut oil. In 1751 and 1768 other 
samples were received through MM. Fresnau and 
Maequer, who sent them to the Academy of Sci- 
ences, Paris, from Cayenne in Guiana. 

Although from this period numerous exj^eriments 
were tried with the new substance little of impor- 
tance was done with it for many years. Its first use 
was to rub out pencil marks, whence it derived its 
name of " india rubber." As late as 1820 this con- 
tinued to be its principal use. 

An interesting reminiscence of its early history is 
given by Joseph Priestley, the great English chemist 
of the last century, celebrated as the discoverer of 
oxygen. In 1770 he mentioned the use of the gum 
for erasing pencil marks, and speaks of its cost 
being three shillings, about seventy cents, for " a 
cubical piece of about half an inch." 

As we have seen, its solubility was early studied. 
In 1761 Herissant added turpentine, ether and 
"huile de Dippel " to the list of solvents. In 1793 
its solubility was utilized in France by Besson, who 
made waterproof cloth. In 1797 Johnson intro- 



AND THE MANIPULATION OF RUBBER. 13 

duced for the same manufacture a solution in mixed 
turpentine and alcohol. 

The year 1820 is the beginning of the period of 
its modern use on a more extended scale. Nadier 
developed the methods of cutting it into sheets and 
threads and of weaving the latter. Mackintosh in 
1823 began the manufacture of waterproof cloth, 
using the solution of the gum in coal tar naptha, 
which was caused to deposit by evaporation a layer 
of the gum upon a piece of cloth which was covered 
by a second one. This protected the wearer from 
the gummy and sticky coating of raw india rubber. 
At the best the original Mackintoshes must have 
been very disagreeable articles for wear. 

In 1825 india rubber shoes of raw india rubber 
were imported from South America and formed for 
a while an important article of commerce. 

In 1839 Charles Goodyear, of Massachusetts, in- 
vented the art of vulcanizing, or combining india 
rubber with sulphur. It was patented on June 15, 
1844, and covers only the manufacture of soft rub- 
ber. Vulcanite or hard rubber (whalebone rubber) 
is disputed as to its origin, its invention being 
assigned by some to Nelson Goodyear and by others 
to Austin G. Day, of Connecticut. Goodyear how- 
ever succeeded in obtaining a patent on May 6, 1851. 
Day obtained a patent on August 10, 1858. 

Vulcanization is the most important invention 
ever made in connection with india rubber and may 
fairlv rank as one of the greatest discoveries of the 



14 HUB BEE HAND STAMP MAKING 

present century. It is claimed by the English, an 
inventor named Handcock being cited as the rival 
of Charles Goodyear. The latter inventor had as 
an associate Nathaniel Hayward, who is probably 
entitled to some of the credit. 

By vulcanization india rubber loses susceptibility 
to heat and cold, becomes non-adherent, and insol- 
uble in almost all substances. It is converted from 
a comparatively useless substance into one of wide 
applicability. 

The subject of india rubber is so interesting in its 
theoretical as well as practical bearings that it 
seems impossible that those who are workers in it 
should not feel an interest in its natural history. 
For such readers the chapter on the natural history 
and collection of india rubber has been written. 
As it is a product of widely separated lands on both 
hemispheres, and as it is yielded by an immense 
number of plants, it is impossible in the limits of a 
chapter to give a full outline of its natural history. 

The chapter in question is, therefore, with this 
apology, inserted where it belongs, near the begin- 
ning of the book. Those who are entirely practical 
may pass it over. There is no doubt that the few 
minutes necessary for its perusal will be bestowed 
upon it by some. 



CHAPTER II. 

THE NATURAL HISTORY AND COLLECTION OF INDIA 

RUBBER. 

• 

African india rubber is mostly exported from 
the west coast. The belt of country producing it 
extends nearly across the continent. Those who are 
familiar with the india rubber plants of our conser- 
vatories are apt to think of the gum as the product 
of trees, but in Africa it is largely yielded by climb- 
ing plants of very numerous varieties, belonging 
generally to the Landolphia species. It is collected 
by the natives by careless or desultory methods, 
probably less advanced than the ways followed by 
the South Americans. Possibly its marked inferior- 
ity may be partly attributed to this. It is also sup- 
posed by many that, were the gathering restricted 
to the vine producing the best gum, better results 
would follow. As it is now all gums are mixed 
indiscriminately. African gum is of very inferior 
quality. 

The African india rubber vines grow often in 
dark moist ravines, where no valuable product other 
than themselves could be cultivated. They are 
entirely wild. The vines when cut exude an abun- 



16 RUBBER HAND STAMP MAKING 

dance of sap, which differs from the South Amer- 
ican product in its quickness of coagulation. As it 
escapes from the wound it at once solidifies and pre- 
vents the further escape of juice. The negroes are 
said to employ the following highly original method 
of collecting it. They make long gashes in the 
bark. As fast as the milky juice comes out they 
wipe it off with their fingers and wipe these in turn 
on their arms, shoulders, and body. In this way 
they form a thick covering of inspissated juice or 
caoutchouc over the upper part of their body. 
This from time to time is removed by peeling. It 
is then said to be cut up and boiled in water. This 
is one account. According to others the natives 
remove a large piece of bark, so that the juice runs 
out and is collected in holes in the earth or on 
leaves. Wooden vessels are said to be used else- 
where. Sometimes the juice is said to be collected 
upon the arms, the dried caoutchouc coming off in 
the shape of tubes. A clew to the inferiority of 
African india rubber is afforded by the statement 
that too deep a cut liberates a gum which deterior- 
ates the regular product if it mixes with it. The 
drying of the gum is thought to have much to do 
with its quality and it is highly probable that this 
affects the African product. Some samples seem to 
be partly decomposed they are so highly offensive in 
odor. The South American rubber is often dried 
in thin layers, one over the other, by a smoky fire, 
which may have an antiseptic effect upon the newly 



A XD THE MAN IP UL A TION OF B UBBER. 1 7 

coagulated caoutchouc. ISo such process as far as 
known is used in Africa. 

The African india rubber appears under different 
names in commerce. From the Congo region lumps 
of no particular shape called ei knuckles " ; from 
Sierra Leone smooth lumps, "negro-heads," and 
"balls " made up of small scrap ; from the Portu- 
guese ports "thimbles/' "nuts," and "negro- 
heads: " from the gaboon (i tongues; " and from 
Liberia "balls are received.''' It is all character- 
ized by great adhesiveness and low elasticity. 

From Assam, Java, Penang, and Rangoon there 
is considerable gum exported. It is supposed to be 
the product of trees of the ficus species, in all these 
places, as it is known to be in Java and Assam. 
In the latter place rigid restrictions are imposed as 
far as possible upon the gathering. In the case of 
wild trees scattered through the forest the carrying 
out of these restrictions is not practicable. The 
trees are cut with knives in long incisions through 
the bark and the juice is collected in holes dug in 
the ground, or often in leaves wrapped up into a 
conical form, somewhat as grocers form their wrap- 
ping paper into cornucopia shape for holding- 
sugar, etc. 

It has seemed reasonably certain that the india 
rubber producing plants might be cultivated with 
profit, and it is as certainly to be feared that 
without such cultivation they will become extinct. 
Efforts have been made in the direction of raisings 



18 RUBBER HAND STAMP MAKING 

them artificially but without much success. In 
Assam numerous experiments have been made to 
propagate the india rubber bearing ficus tree. 

A good instance of the ill effects of carelessness 
in the original gathering of the crop is afforded 
by the Bornese collectors. The source of Borneo 
india rubber is a variety of creepers. These are cut 
down and divided into short sections from a few 
inches to a yard in length. The sap oozes out from 
the ends. To accelerate its escape the pieces are 
sometimes heated at one end. It is coagulated by 
salt water. Sometimes a salt called nipa salt, ob- 
tained by burning a certain plant {nipa fruticans), is 
used for the purpose. In either case it is coagulated 




Tree Felled for Collection of India Rubber. 

into rough balls and masses. These masses are 
heavily charged with the salt water, often contain- 
ing as much as fifty per cent., and rarely much less 
than twenty per cent. 

Central America and Panama are great producers 
of the gum. In Panama the custom of felling the 



AND THE MANIPULATION OF RUBBER. 19 

trees is often adopted. In this case grooves are cut 
around the prostrate trunk, and under each groove 
as the trunk lies on the ground a vessel is placed to 
collect the sap. Its coagulation is often effected by 
leaving it for a couple of weeks standing at rest in a 
hole, excavated on the surface of the ground, and 
covered over with leaves. The caoutchouc sepa- 
rates under these conditions. A quicker method, 
but one yielding an inferior product, is obtained by 
adding to the fresh juice some bruised leaves of a 
plant (iponwa bona nox) which acts something 
like acid upon milk, in separating the desired solid 
matter or caoutchouc. A jelly like accretion satu- 
rated with blackish water is thus obtained. By 
working it together a blackish liquid is caused to 
escape, and comparatively pure gum is gradually 
obtained. As much as one hundred pounds of 
india rubber may be obtained from a single tree 
where this destructive system is employed. Fur- 
ther north, where a better counsel has prevailed, the 
trees are only tapped, and the india rubber hunter 
is satisfied if from a tree eighteen inches in diam- 
eter he obtains twenty gallons of sap, giving fifty 
pounds of gum. Even where tapping is done the 
tree is often destroyed by carelessness or ignor- 
ance. 

Two systems are followed in Nicaragua. The oper- 
ator ascends by a ladder if he has one, or in any case 
climbs as high as he well can and begins to make a 
long incision. Sometimes he carries one long straight 



20 RUBBER HAND STAMP MAKING 

cut clear down to the ground. This is made the 
starting point for a number of side cuts, short, and 
running diagonally into it. This is also one of the 
Brazilian methods. The Nicaraguan sometimes 
also makes two spiral incisions, one right-handed 
and the other left-handed, crossing each other as 
they descend so as to divide the surface of the tree 
into roughly outlined diamonds. In either case the 
juice flows down to an iron spout, placed at the 
bottom of the tree, which sj)Out leads to an iron 
pail. The milk is gathered and passed through a 
sieve, and coagulated in barrels by the ipomcea plant 
as before mentioned. This gives three grades of 
rubber. The bulk is obtained from the barrels and 
is called often meros; the small lump which forms in 
the spout is rolled into a ball and called cabezza; 
the dried strips pulled out of the cuts is of very 
good quality and is called bola or burucha. 

From Brazil is exported the famous Para iudia 
rubber. This is of very high quality, and is greatly 
esteemed by all manufacturers. No process can 
make a poor gum give a really good product. The 
system of gathering it varies. Sometimes the tree 
is cut into by gashes from an axe, such gashes ex- 
tending in a row all around the trunk. Under each 
gash a small clay cup is luted fast with some fresh 
mixed clay. These collect from a tablespoonful of 
juice upward, which is collected, and the cups are 
removed on the same day. The next day a second 
row of cuts is made below the others, and the same 



AND THE M . i N I P UL A TION OF R UBBEE. 2 1 



process is repeated. This is continued until from a 
point as high as a man can reach, down to the 
ground the tree is full of cuts. Sometimes a gutter 
of clay is found partly around the trunk with 
gashes above it. In other cases a vine is secured 




?5^ 



Tree Tapped for India Rubber. 

around the tree and a collecting gutter is worked 
with it for a basis. 

The juice is coagulated in a smoky fire. A bot- 
tomless jar is placed over the fire and some palm 
nuts are mixed with the fuel. The mould, which is 
often a canoe paddle, is smeared with clay to pre- 
vent adhesion and is then heated. A cup of juice 
is poured over it, and after the excess has dropped 
off it is moved about rapidly over the smoke and 



22 



RUBBER HAND STAMP MAKING 



hot air which ascends from the mouth of the jar. 
This series of operations is repeated until the coat- 
ing is quite thick; it may be as much as five inches. 
After solidifying over night it is cut open and the 
paddle or mould is removed. After a few days dry- 




Indian Drying and Smoking India Rubber. 

ing it is sent to market. With all the heating, 
during which it sweats profusely, it still retains 
fifteen per cent, of water. 

India rubber sap may be coagulated by an aqueous 
solution of alum. The process has been tried in 
Brazil, and is used to a considerable extent in 



AND THE MANIPULATION OF RUBBEli. 23 

Pernambuco. It was proposed by an investigator 
named Strauss, and the process is still called by his 
name. One objection is that it gives a very wet 
product, and apparently one of inferior value to the 
smoked gum. 

The feeling that india rubber suffers in the gath- 
ering has been so much felt that it has been re- 
cently suggested that if possible the uncoagulated 
juice should be exported to Europe there to be 
worked up from the beginning. 



CHAPTER III. 

PROPERTIES OF UNVULCANIZED AND VULCANIZED 
INDIA RUBBER. 

There are two broad divisions to which all varie- 
ties of india rubber can be assigned — nnvulcanized 
and vulcanized rubber. Speaking with a certain 
amount of license it may be said that more proper- 
ties characterize the former than the latter. The 
vulcanized article is very slightly affected by ordi- 
nary changes of temperature, cannot to any consid- 
erable extent be changed by heat short of absolute 
destruction or decomposition, cannot be united or 
moulded except in simple forms, is highly elastic, 
and is insoluble in almost every solvent for ordinary 
caoutchouc. 

Unvulcanized caoutchouc possesses very interest- 
ing and peculiar properties. The first part of the 
present chapter is devoted to this substance. Those 
who have never seen the crude gum as imported are 
familiar with the article almost pure in the form of 
sheet rubber and black rubber articles generally. 
These are of nearly pure caoutchouc, though recently 
the tendency is to vulcanize them to a considerable 
degree. 



AND THE MANIPULATION OF RUBBER. 25 

A piece of pure gum containing no combined 
sulphur, iodine, or other vulcanizing constituent 
will be found to exhibit a very striking peculiarity. 
Two freshly cut surfaces when placed in contact 
will adhere. This is not in consequence of any 
viscous or sticky coating. When india rubber is 
cut the surface is perfectly dry and non-adherent 
except to itself. 

The writer once had this property of adhesion 
brought strongly to his attention. In some analyt- 
ical investigations of coal gas he had proposed to 
use finely divided india rubber as an absorbent of 
sulphur. This constituent it absorbs from gas. and 
it seemed that a basis for a quantitative determina- 
tion of sulphur might be found in such property. 
Accordingly some raw india rubber was procured 
and with some trouble was cut up into little pieces 
which were put into a bottle. A day or two after- 
wards the pieces united wherever they were in con- 
tact, and an irregular cavernous lump was the 
result. This involved no melting or softening or 
change of shape. Each little piece was there intact 
and distinct but firmly attached to its neighbors. 

The analogy of this action is seen in lead. Two 
fresh surfaces brought together, preferably with a 
twisting or wrenching pressure, adhere quite firmly. 
The adherence of india rubber and of lead each to 
itself is often exhibited by physical lecturers as an 
illustration of cohesion. The cohesion of india 
rubber is however far more perfect than that of 



26 RUBBER HAND STAMP MAKING 

lead, probably because of its comparatively great 
resistance to oxidation, and because, owing to its 
elasticity larger areas can be brought in contact. 
Comparatively great though this resistance to oxi- 
dation is, oxygen, especially in the allotropic modi- 
fication known as ozone, may act quite powerfully 
on the gum. Sunlight also can affect it injuri- 
ously. 

A more familiar illustration of the uniting of two 
pieces of the same material is seen in the welding 
of iron. The blacksmith heats two pieces of iron 
until they are nearly white hot and are pasty in 
consistency. On placing them in contact and ham- 
mering to force them together they unite so firmly 
as to be practically one. It is necessary that the 
surfaces of clean metal should be brought together. 
If the pressure induced by the hammering is insuf- 
ficient to bring this about, a flux is added which 
dissolves the oxide and causes the metal to come in 
contact with metal and to weld. The analogy with 
india rubber in its cohesive action is evident. Sur- 
faces long exposed or which are dusty do not cohere. 
The regelation of ice is similar in effect. 

The cohesion of india rubber is important and 
should be thoroughly appreciated. It is not saying 
too much to assert that the entire treatment of the 
raw gum depends upon this interesting property. 
The great lumps of gum are torn to pieces and 
washed free from gravel and dirt without going to 
powder, because owing to their elasticity they yield 



AND THE MANIPULATION OF BUBBER. 27 

and as fast as torn apart the pieces tend to reunite. 
Again india rubber is mixed with pigments and vul- 
canizing reagents by a method practically one of 
grinding or masticating, but the material while it 
changes its shape, and by the admixture of the. va- 
rious ingredients becomes less strong or easier torn, 
still remains intact, as it welds together or coheres 
as fast as disintegrated. 

As regards its chemical constitution the sap of a 
Para rubber tree has been analyzed with the follow- 
ing general results: (Faraday). 

Caoutchouc 80.70 

Albuminous, extractive, and saline matter, etc 12.93 

Water 56.37 

100.00 

Its specific gravity is 1.012. 

Caoutchouc itself or raw india rubber is a mixture 
of several hydrocarbons of the following composi- 
tion in general: 

Carbon 87.5 

Hydrogen 12.5 

100.0 

Its specific gravity is from .912 to .942. 

The hydrocarbons composing it are isomeric or 
polymeric with turpentine. This fact brings it well 
within the range of familiar vegetable products. 
As will be seen the products of its distillation fall 
among the same polymers and isomers. 



28 RUBBER HANB STAMP MAKING 

When pure it is nearly colorless, the dark color 
being due to impurities. In thin sheets it is almost 
or quite transparent. It burns readily, and with a 
very luminous, smoky flame, as might have been 
anticipated from its composition. The action of 
heat and cold on it is dependent on the degree of 
the temperature. At ordinary temperature it is 
elastic and firm. It can be stretched and will re- 
turn almost to its original size when released from 
tension. Yet the return to its shape is so liable 
to be incomplete, especially after long sustained 
stretching, that pure unvulcanized india rubber is 
considered imperfectly elastic. 

Any elasticity it possesses is principally elasticity 
of shape as distinguished from elasticity of volume. 
In other words when pressed or stretched it may 
change shape to a great extent but hardly change 
its volume at all. A cube of 2^ inches under a 
weight of 200 tons lost 1-10 of its volume only. 
This is largely due to the fact that it represents an 
approximately solid body, or one destitute of consid- 
erable physical pores. Solids and liquids are very 
slightly compressible. Whatever degree of com- 
pressibility caoutchouc possesses is due principally 
to its minute pores. 

If the temperature is reduced to the freezing 
point of water a piece of raw india rubber becomes 
rigid and stiff. On application of heat it returns to 
its former pliable condition. The same return to 
flexibility may be brought about by stretching it 



AND THE MANIPULATION OF RUBBER. 29 

mechanically. This may be rather a fallacy. 
Stretching india rubber warms it, so that in this 
mechanically imparted rise of temperature we may 
find at least a probable cause of the softening. 

If the temperature is raised several effects are 
produced, according to circumstances. A piece 
which has been stretched and held stretched, has its 
tension increased by a degree of heat considerably 
less than that of boiling water. Some offer the 
theory that it contains air enclosed in its pores 
which, expanding, produces this effect. As the 
boiling point is reached the material softens and 
becomes somewhat plastic, so that it can be moulded 
into shape to a considerable extent and stretched to 
threads of great fineness. Its elasticity also disap- 
pears as the heat is maintained. These effects in- 
crease in extent up to a heat of 248° F. (120 3 C). 
The return to its original state is not immediate 
however. Some time is required before the reduc- 
tion of temperature will have full effect. 

If now a still higher degree of heat is applied, 
392° F. (200° C.) the india rubber softens to a 
viscous body, or melts. From this state it cannot 
be restored. It remains permanently "burned" or 
melted whatever is done to it. Some attempt at 
hardening may be made by the use of vulcanizing 
chemicals, but the result will be very imperfect. 

A further increase of heat brings about a destruc- 
tive distillation. India rubber treated in a retort to 
a heat exceeding 400° F. (204° C.) evolves volatile 



BO EUBBEli HAND STAMP MAKING 

hydrocarbons of oily consistency, and it distills 
almost completely, a small residue of gummy mat- 
ter or of coke if the final heat has been pushed far 
enough being left. The distillate is called caout- 
choucin. According to Mr. Greville Williams it con- 
sists of two polymeric hydrocarbons : one, caout- 
chin C 10 H 16 , boiling point 340° F. (171° C); the 
other, isoprene C 5 H 8 (in formula equal to one-half 
of caoutchin), boiling point 99° F. (37° C). The 
mixture has a strong naptha-like odor and has won 
considerable reputation as being the best solvent for 
india rubber. How far it deserves its reputation is 
a matter open to discussion. 

The solution of india rubber like its fusion is a 
vexed point. There is little question that it can be 
dissolved by proper treatment. Usually naptha, 
carbon disulphide or benzole are used as solvents, the 
choice being guided by motives of cheapness and 
efficiency. 

It is worthy of remark that the formula given for 
caoutchoucin is the same as that of the principal 
constituent of oil of turpentine, and that the latter is 
often recommended as a solvent. Turpentine is 
slightly more volatile than caoutchoucin, its boiling 
point being 322° F. (161° C.) Other hydrocarbons 
have been recognized in the distillate by Bou- 
chardat, Himly and G-. Williams, varying in boiling 
point from 32° F. (0° C.) to 599° F. (315° C), and in 
specific gravity from 0.630 to 0.921. 

Although it has been spoken of as approximately 



AND THE MANIPULATION OF RUBBER. 31 

solid it does possess microscopic pores, to which its 
limited amount of elasticity of volume is mostly 
due. Thus it is found to absorb water, in which it 
is quite insoluble. As it does this it acts like a dry 
sponge and increases in volume a little, owing to 
dilation of these minute pores. The water absorbed 
may be as much as 18.7 to 26.4 per cent, with an in- 
crease of volume of the gum of i&h> to T Mo. When 
it has once absorbed water it is very hard to get rid 
of it. Although the minute surface orifices commu- 
nicate with the entire system of capillary vessels 
and pores, the surface pores on drying contract and 
seal up the absorbed water within the mass. This 
is a clew to the impracticability of the gatherer ship- 
ping dry rubber, and to the great difficulty the 
manufacturer experiences in drying his washed and 
sheeted stock before working it up by masticating 
or mixing and curing. 

By proper manipulation caoutchouc may be made 
inelastic. This can be done by the freezing process 
or by keeping it stretched for two or three weeks. 
In this way threads can be made to extend and to 
remain extended to seven or eight times their orig- 
inal length. They can then be woven into a fabric. 
On gentle heating their original elasticity reappears 
and they contract. In this way fluted braids can be 
made which will have a high capacity for stretch- 
ing. 

The solution of caoutchouc is difficult often to 
bring about. We have seen that in water it swells 



32 RUBBER HANI) STAMP MAKING 

a little without dissolving. In benzole it does the 
same, but swells to a greater extent, to 125 times its 
original volume or even more. Some authorities 
( Watts) go so far as to assert that no solvent com- 
pletely dissolves it. Acting on it repeatedly with 
benzole or other solvent and taking care not to 
break up the swelled mass, from 49 to 60 per cent, 
of soluble matter can be extracted. On evaporation 
this is deposited as a ductile adherent film. The 
swelled up residue which remains undissolved is 
assumed to be the constituent giving strength and 
elasticity, and is only sparingly soluble. If the 
gum is masticated or kneaded at the temperature of 
boiling water a change occurs not well understood, 
by which its solubility is greatly increased. As 
solvents many liquids have been named. Oil of 
turpentine, caoutchoucin, coal-tar, naptha, benzole, 
petroleum-naptha, coal-tar-naptha, anhydrous ether, 
many essential oils, chloroform, bisulphide of car- 
bon, pure, or mixed with seven or eight per cent, of 
alcohol, are among the solvents recommended. A 
mixture of fifty parts ot benzole and seventy parts 
of rectified turpentine has been given as a solvent 
for twenty-six parts of the gum. Mastication be- 
fore or after immersion in the solvent is to be 
advised. More will be said on this subject in a 
succeeding chapter. 

Vulcanized india rubber is unaffected by changes 
of temperature within ordinary range. It softens a 
little on heating. Even hard vulcanite when heated 



AND THE MANIPULATION OF RUBBER. 33 

can be bent and will retain the bend on cooling. 
It is exceedingly elastic with elasticity of shape but 
far less compressible as regards absolute change of 
volume than the raw gum. It melts at 392° F. 
(200° C.) It cannot be made to cohere, and no 
cement has yet been discovered that will satisfac- 
torily unite two surfaces. It is unaffected by light, 
by ordinary acids and rubber solvents. In contact 
with the latter solvents it swells sometimes to nine 
times its original volume, but on heating returns to 
its original volume and shape. Of water it will 
absorb no more than four per cent, and often much 
less. If it is maintained at a high temperature 
266° to 302° F. (130° to 150° C.) for a long time it 
gradually loses its flexibility, especially if in con- 
tact with metals. Often the escape of sulphuretted 
hydrogen may be observed under these conditions. 
A small admixture of coal tar operates to prevent 
this action. 

Its composition and specific gravity vary widely 
as the most varied mixtures are added by the manu- 
facturer. Its relation of carbon to hydrogen is 
unaffected by the mixtures added. While it may 
contain twenty per cent, or more of sulphur it is 
believed that but a very small quantity is combined 
with it, although the excess of sulphur or some 
equivalent, such as sulphide of antimony is essen- 
tial to vulcanization. The combined sulphur is 
from one to two per cent. Some or all of the ex- 
cess of sulphur is mechanically retained, and as the 



34 BUB B Eli HAND STAMP MAKING 

rubber in ordinary use is worked about, keeps escap- 
ing and forms a whitish dust upon the surface. By 
treatment with alkali some of the excess of sulphur 
can be removed when the rubber acquires the power 
of absorbing a little more water, up to six and four- 
tenths per cent. 

Boiling oil of turpentine is given as its solvent. 



CHAPTER IV. 

THE MANUFACTURE OF MASTICATED, MIXED SHEET, 
AND VULCANIZED INDIA RUBBER. 

The manufacture of india rubber relates to the 
production of two principal products. One is mas- 
ticated unvulcanized sheet and thread rubber; the 
other is un masticated mixed and cured rubber, 
otherwise vulcanized rubber. For the purposes of 
the rubber-stamp maker an intermediate product is 
required, namely, unmasticated mixed sheet which 
is uncured. This is really incompletely vulcanized 
india rubber. 

It will be evident from the description to come 
that it is not advisable for any one without consider- 
able apparatus to attempt to clean and to wash (" to 
sheet"), to masticate, or to mix india rubber. 
These operations are best accomplished in the fac- 
tories. The partially vulcanized (''mixed sheet") 
or the pure masticated article are regular articles of 
commerce. Yet a full insight into the manipula- 
tion of india rubber can only be obtained by under- 
standing its treatment from the gum up to the two 
separate lines of products we have indicated. 

A third type of product is coated tissue, such as 



36 RUBBER HANB STAMP MAKING 

Mackintosh. This really is a sequence of one of 
the other two processes and a few words will be said 
of it in concluding the chapter. 

As the caoutchouc is received' by the manufac- 
turer it appears an utterly intractable mass. It 
occurs in lumps of every size, varying in color and 
odor, and very tough but elastic. In virtue how- 
ever of the properties already described, its power of 
cohering when cut, and its softening when heated, 
it becomes amenable to treatment. 

It is to some extent received in such assorted 
condition as to secure even grades, and then each 
grade may be washed by itself. It is thrown into 
water which is in many cases kept at the boiling 
point by steam-heat and left there for some hours. 
It absorbs some water and also softens. Some gum 
is so soft that it will not stand hot water. For such 
the water is kept cold. The purer gum floats; such 
pieces as have stones, dirt, iron, etc. in them, per- 
haps placed there purposely from fraudulent motives, 
sink and can be picked out for separate treatment. 

The lumps are next cut up. A revolving circular 
knife driven by power is often used, and sometimes 
an ordinary knife is adopted. At this part of the 
operation there is frequently need for sorting, as the 
grades received may have inferior pieces mixed witli 
the good. The cutting is mainly to secure good 
grading, and to remove concealed impurities. The 
gum then goes to the washing rollers, called the 
washer and sheeter. (See cut, p. 37.) 



AND THE MANIPULATION OF RUBBER. 37 

These are heavy corrugated rolls made very short, 
9-18 inches in length, to prevent springing. They 
are grooved or corrugated and have a screw adjust- 
ment for regulating their distance apart. They 
are geared together so as to work in corresponding 
directions, like a clothes wringer or a rolling mill 
of any kind. The pieces of gum are fed into the 




Washer and Sheeter. 

roils and are drawn between and through them. 
The friction tends to heat the gum. To prevent 
this and also to effect the washing, a supply of 
water, either hot or cold, is kept playing upon the 
mass. This dissolves out all soluble matter and 
washes away mechanically the chips, dirt, etc. 
which may be present. The whole operation is one 
of main force. The caoutchouc is torn and dis- 
tended and delivered as a rough perforated sheet. 
It is passed repeatedly through the machine, the 
rollers being gradually brought closer together, or 
else different sets of rolls are used, set to different 



38 



RUBBER HAND STAMP MAKING 



degrees of fineness. The wash water passes through 
a screen which catches any small detached frag- 
ments of gum. 

Other types of machines have been introduced; 
the above is a representative form. 

The rough sheets must now be perfectly dried, as 
water impairs the final product. This is done in 
drying rooms by steam heat, generally, at a temper- 
ature of about 90° F. (32° 0.) The windows, if 
there are any, are painted to exclude sunlight, which 
operates to deteriorate raw gum. When absolutely 
dry the caoutchouc is removed and stacked away 
for use. 




Masticating Machine. 



To prepare pure gum for the manufacture of 
sheet rubber and as a starting point for many other 
preparations, the india rubber is " masticated " in 



AND THE MANIPULATION OF RUBBER. 39 

special apparatus. The machine consists of a fixed 
cylinder within which is a corrugated roller set 
eccentrically and rotated by power. The perfectly 
dry sheets in the masticator are pressed and rolled 
and ground and produce a mass of even consistency. 
Here the welding or cohering action again appears 
in its fullest development. The perfect dryness of 
the mass enables it to keep reuniting as fast as 
divided. The action is assisted by the heat gener- 
ated, which is not inconsiderable. Sometimes the 
caoutchouc is warmed before introduction, and 
sometimes the roller is heated by passing steam 
through it. 




Masticating Machine. 

The masticating machine the French pictur- 
esquely term the wolf (Joup) or devil ((liable). It is 
given from sixty to one hundred turns a minute, 
and a machine large enough to treat fifty pounds of 



40 BUBBEli HAND STAMP MAKING 

gum in a charge, requires five horse-power to drive- 
it. In it the sheeted gum is ultimately brought to 
the state of a perfectly homogeneous dark brown 
translucent mass. 

The masticated rubber is peculiarly amenable to 
mechanical and chemical treatment. It can fee 
shaped by heat and pressure, and it is the most 
soluble form and is used for making cement and 
solution, and is moulded into blocks for the manu- 
facture of sheet and thread rubber. In the process 
neutral body pigments, such as oxide of zinc, or sol- 
uble transparent ones, such as alkanine may be intro- 
duced; easily decomposed matter cannot be incorpo- 
rated on account of the heat. 

In all these machines special provision is made 
to prevent any oil from getting into the gum. 
There is no greater enemy to india rubber than oil 
or fats of any description. The flanges in the mas- 
ticator that roll just inside the bearing are for this 
purpose. 

Sheet rubber is made from the blocks of masti- 
cated gum by slicing. A machine is used for the 
purpose which carries a knife which works back 
and forth in the direction of its length at high 
speed, making two thousand cuts a minute. The 
knife is kept wet by a stream of water, and about 
sixty cuts are made per inch. In many articles 
made from this sheet the marks of the cuts can be 
seen as a fine ribbing. The appearance is familiar 
to many readers. 



AND THE MANIPULATION OF RUBBER. 41 

The sheet is often cut from rectangular blocks, 
but cylindrical blocks are also used. The latter are 
rotated in front of the knife edge and a long, con- 
tinuous sheet can thus be obtained. 

The sheet rubber can be cut into threads on web- 
bing and braid. Everyone has noticed that these 
threads are usually square. The method of prepa- 
ration accounts for it. Vulcanized sheet is now 
almost universally used for threads. 

Round threads however can be made by forcing 
softened or partly dissolved gum through a die. 

It is from unvulcanized masticated sheet that 
toy balloons, tobacco pouches, etc., are made. It is 
the starting point for india rubber bands. For the 
usual form of the latter article the sheet is cemented 
into a long tube which is afterwards cut transversely, 
giving bands of any desired width. To make any 
of these articles satisfactory vulcanization is imper- 
ative. Uu vulcanized rubber for many years was 
used, but it is "now completely displaced by the 
vulcanized product. Sheet rubber is made as above; 
is vulcanized by some of the absorption processes 
described in the chapter on vulcanization. 

We now come to the second product: regularly 
mixed and cured rubber. Its starting point is 
the washed india rubber from the washer and 
sheeter. 

We have seen that the pure gum or caoutchouc is 
very sensitive to changes of temperature. At the 
freezing point of water it is hard and rigid, and at 



42 



EUBBEB HAND STAMP MAKING 



the boiling point is like putty in consistency. 
There are several substances which can be made to 
combine with the gum and which remove from it 
this susceptibility to change of temperature. The 
process of effecting this combination is called vul- 
canization, and the product is called vulcanized 
india rubber. Sulphur is the agent most generally 
employed. 

In the factory the normal vulcanization is carried 
out in two steps, mixing and curing. The washed 
sheet india rubber which has not been masticated 
and which must be perfectly dry is the starting 




Making Mixed Rubber. 



point, and the mixing rolls shown in the cuts are the 
mechanism for carrying out the first step. These 
are a pair of powerful rollers which are geared so as 
to work like ordinary rolls, except that one revolves 



AND THE MANIPULATION OF RUBBER. 43 

about three times as fast as the other. They are 
heated by steam, which is introduced inside of 
them. The sheet is first passed through them a 
few times to secure its softness, and then the opera- 
tive begins to sprinkle sulphur upon it as it enters 
the rolls. This is continued, the rubber passing and 
repassing until perfect incorporation is secured. 
About ten per cent, of sulphur is added, and a work- 
man can take care of thirty pounds at a time. 

This material is incompletely vulcanized. It is 
in its present condition very amenable to hetit and 
is ready for any moulding process. Generally it is 
rolled out or " calendered " into sheets of different 
thickness from which articles are made in moulds 
by curing. 

These sheets are of especial interest to the reader 
as they are the material from which most small arti- 
cles are made, including rubber stamps. 

This rolling of the mixed india rubber into sheets 
of definite thickness is done by special calendering 
rolls. The product is termed " mixed sheet." 

In the mixing rolls the incorporation of other 
material is often brought about. Zinc white, lead 
sulphide, antimony sulphide, chalk, clay, talc, 
barium sulphate, plaster of paris, zinc sulphide, 
lead sulphate, white lead, oxides of lead, magnesia, 
silica, form a list of ordinary mixing ingredients. 
These lower the cost of the finished material and are 
often serious adulterants. For some cases the addi- 
tion if not carried too far is not injurious, or even 



44 



RUBBER HAND STAMP MAKING 



may be beneficial. A proper admixture renders the 
gum more easily moulded and treated in the shap- 
ing processes. 




Mixing Rolls. 

The next step in the vulcanizing process is the 
heating of the mass, which step is called " curing. " 
Up to a temperature in the neighborhood of that of 
boiling water the mixed rubber can be heated with- 
out change except as it is softened. But if the heat 
is increased it begins to get a little more elastic and 
less doughy, and eventually becomes i( cured " or 
vulcanized. The temperature for vulcanization is 
about 284° F. (140° C). The word " about " is used 
advisedly, for it is not only a question of heat but of 
time of exposure. After vulcanizing, including the 
curing, india rubber cannot be moulded to any 
great extent. In the manufacturing process, there- 
fore, it is before curing placed in the moulds, 



AND THE MANIPULATION OF RUBBER. 45 

heated, shaped by pressure, and by exposure to a 
higher heat in a steam oven called a vulcanizer, is 
at once cured. 

To prevent adherence to the moulds they are 
dusted over with ground soapstone, and the rubber 
itself is often thus coated. 

The methods of vulcanization and curing, which 
may be of special use to the reader, are given in the 
chapters devoted to that subject (chapter XL), and 
in the one devoted to rubber stamps. 

Hard rubber, termed ebonite when black, and vul- 
canite when of other colors, is simply vulcanized 
rubber containing a large percentage of sulphur 
added in the mixing process. 

The manufacture of coated tissues is effected in 
several ways. The following is a typical process. 
A mixture of one part washed and sheeted india 
rubber with one part zinc white, one fourth part 
sulphur, and about one third part naptha is mixed 
into a dough-like mass and is spread upon the cloth 
by machinery. The latter is simple. It consists of 
a bare board arranged to move under a scraping bar. 
The cloth is placed on the board and carried under 
the bar. The coating mixture is fed on one side of 
the bar upon the surface of the cloth. As it passes 
under, a regulated amount, according to the set of 
the bar, adheres. It is then dried by steam heat 
and recoated, until ordinarily six coats, each about 
one one-hundreth of an inch in thickness, have been 
given. Three coats are given in each direction with 



46 RUBBER HAND STAMP MAKING. 

intermediate drying. The fabric is then cured by 
heat in vulcanizers. 

Sometimes the sulphur is omitted from the mix- 
ture and cold curing, as described later, is adopted. 
When the goods are made up the seams are secured 
with rubber cement, a thick solution of masticated 
gum. Such seams have to be vulcanized. 

Sometimes two such fabrics before curing or vul- 
canization, are placed face to face and allowed to 
adhere and are then cured or vulcanized. 

Enough has been said in this outline of the man- 
ufacturer's treatment of india rubber to show that, 
the first treatment requires machinery. Very little 
can be done with mortar and pestle, although in 
making up solution these simple instrumentalities 
are available. As a starting point for making small 
articles masticated sheet rubber and mixed sheet 
rubber are the staple materials. The preceding 
steps are best accomplished in the factory. 



CHAPTER V. 

INDIA RUBBER STAMP MAKING. 

We have seen that india rubber cannot be cast in 
moulds. Except in special cases deposition from 
solution is not available. It has to be shaped by a 
combination of heat and pressure. When gently 
heated it softens and can be tressed in a mould. 
As it cools it retains the shape thus given and is 
moulded. This applies to all un vulcanized india 
rubber. If mixed rubber is moulded and heated to 
a higher temperature without removal from the 
mould the curing process is brought about and the 
rubber may be not only moulded but cured and the 
product is moulded vulcanized india rubber. The 
mixed sheet whose manufacture is described in 
chapter IV. (page 42) is the starting point in rub- 
ber stamp making. It is made for this purpose by 
the manufacturers. 

When the material is examined it looks like ordi- 
nary white india rubber, being firm in texture and 
quite strong. On heating to 280° F. to 290° F. 
(137° C. to 143 c 0.) it begins to become "cured/' 
and if in a thin sheet one to ten minutes are suffi- 
cient for the process. As the heat is applied the in- 



48 RUBBER HAND STAMP MAKING 

dia rubber first softens and becomes much like putty. 
It can now be pressed through the smallest . orifice 
and will fill up the finest details of anything it is 
pressed against. It is at this point that pressure 
must be applied to drive it into the interstices of 
the mould. 

As the heat continues it begins to lose its doughy 
or putty-like consistenc}^. This marks the 'reaction 
of the vulcanizing materials. They gradually com- 
bine with and change the nature of the caoutchouc. 
The rubber while still quite soft is elastic. If 
pressed by the point of a knife it yields, but springs 
back to its shape when released from pressure. The 
india rubber is vulcanized. 

On removal from the mould it will be found to 
reproduce its smallest detail. The color and ap- 
pearance have not changed much, but its nature 
and properties are now those of vulcanized rubber. 
It is unaffected by heat or cold within ordinary 
ranges of temperature, and if the india rubber is of 
good quality and made by a proper formula it will 
last for years. 

The first thing to be described is the mould, 
which includes the arrangements for pressing the 
sheet of india rubber while heated. A small press 
is needed for this purpose. It may be of the sim- 
plest description, and as an example of a home- 
made but perfectly efficient one the illustration 
may be referred to. The base of the press is a piece 
of iron, if heat is to be directly employed. Where a 



AND THE MANIPULATION OF BIBBER. 40 



chamber vulcanizer is used both base and platen 
may be of wood. But from every point of view iron 
is the best. It lasts forever, admits of direct heat- 
ing, and does not split, warp, or char. Through 
two holes drilled near its opposite sides two or- 
dinary bolts are thrust. It is best to use flat 
headed bolts, and to countersink a recess for the 




Simple Vulcanizing Press for Rubber Stamps. 

heads in order to keep the bottom level. The heads 
may need to be filed off so as to reduce their thick- 
ness, in order to secure this object. The bolts may 
be soldered in place. One thing should be care- 



50 BUB BE H HAND STAMP MAKING 

fully watched for — the bolts should be set true so as 
to rise vertically from the plane of the base. 

The platen is best made of iron, cut of the shape 
shown. This is an excellent disposition of the 
screw-bolt slots, as by swinging the right end of the 
platen back it can be taken off without removing 
the nuts and lifting it over the ends of the screws. 
Besides the two nuts fitting the thread of the screws 
it is well to have half a dozen extra ones larger than 
the others, which will slip easily over the bolts, so as 
to act as washers. The object of these is to adapt 
the press to objects of different thickness. The 
thread upon an ordinary bolt does not extend clear 
to the head, but by slipping on some loose nuts the 
plates can be forced together if desired. 

This press can be simplified. Both base and 
platen can be made of wood, the platen being sim- 
ply bored for the bolts, and the latter driven tightly 
through the holes in the base so as to retain their 
place. Even this can be improved on as regards 
simplicity. Two blocks of wood screwed together 
by two or more long wood screws may be made to do 
efficient work. 

One trouble is apparent with all these devices, 
and that is the want of parallelism of the opposed 
planes. The base and platen may be true and 
parallel or they may not. Perhaps the simplest 
way of securing this is the best. It consists in 
placing across the base two distance pieces, which 
may be slips of wood. These must have perfectly 



AND THE MANIPULATION OF RUBBER. 51 

parallel faces. As the press is screwed up they will 
be gripped between the platen and base and will 
not only ensure their parallelism but will keep them 
at an exact distance apart. Such distance pieces 
are shown in the same cut. Pieces of printers' 
"furniture," spaces, or "quads," may be used for 
this purpose. They should not be fastened in place 
if there is need to adapt the press to more than one 
thickness of material and matrix. 

The above described apparatus is a vulcanizing 
press. A further improvement in it may be effected 
by the use of spring pressure. Two strong spiral 
springs may be dropped over the bolts, the nuts 
being screwed on above them, or a powerful spring 
of flat brass or steel ribband bent into the shape of 
a shallow letter V may intervene between nuts and 
platen, the centre of the bend bearing against the 
centre of the platen. 

As regards the strength of the springs there is 
this to be said. The distance pieces will prevent a 
spring that would ordinarily be too powerful from 
doing any harm. Such distance pieces should be 
used, as the springs must be based upon giving a 
pressure of many pounds per square inch of surface 
to be acted on. They should have a range of an 
eighth of an inch or more. The greater the range 
the more evenly will they work. 

The next cut shows an excellent little screw press, 
that is made for the purpose of pressing vulcanizing 
flasks. This is so simple that it will suggest to the 



52 BUB BEE HAND STAMP MAKING 

mechanical reader how lie can make a single-screw 
press, which is by far the most convenient to use. 
In the stationery stores very small model cast iron 
copying presses designed for use as paper weights 
are sold. They are excellent for a limited amount 
of small sized work. 




Vulcanizing Flask Clamp, 

A large sized gas heated press, such as made for 
the purpose of manufacturing rubber stamps, is 
shown in the next cut, p. 53. Its construction is 
obvious. It is termed by the trade a vulcanizer. Its 
manipulation will be given further on. 

Type are generally the object to be copied. 
These are best set up with high quads and spaces. 
Naturally rather a large type is chosen, with extra 
wide spaces between the letters. Some advise rub- 
bing the type faces full of hard soap, afterwards 
brushing off the face, leaving the hollows filled. 
Sometimes wax is recommended for the same pur- 



A ND THE MAN1P ULA TWN OF li UBBER. 53 

pose. This prevents the plaster of the matrix en- 
tering so deeply into the cavities of the letters. 

The type forming the model to be reproduced, is 
locked in a frame. Two pieces of printers' furni- 




Gas-heated Stamp Vvlcanizer. 

ture or other wooden strips screwed together by 
wood screws at their ends will answer for a lockir.g 
frame for small inscriptions. 

The model to be copied need not be type, but any 
desired relief may be used, such as an electrotype, a 
stereotype, an engraving or another rubber stamp. 
In any case it is to be placed upon a flat surface, 
best an "imposing stone" or piece of marble, with 



54 BUBBEB HAND STAMP MAKING 

the inscription upwards. On each side of it dis- 
tance pieces reaching about one-eighth inch above 
its upper surface are to be placed. 

The next shaping appliance is the matrix or 
mould, or reverse of the model which is to be 
copied. This in the case of rubber stamps is prop- 
erly called the matrix. Those who have witnessed 
the stereotyping of a large daily newspaper have 
seen the matrices of the type made of paper and 
paste, the whole mixture being termed " Hong." 
Such a matrix is required for rubber type, but 
paper is rather too susceptible to heat although good 
work can be done with it. It also does not enter as 
deeply into the cavities of the type as is desirable. 
As a rule a fine quality of plaster of paris is to be 
recommended. What is sold as dental plaster is 
the best, but common plaster can be used. It is 
mixed with water or with a solution of gum arabic 
or dextrine in water. For the latter enough gum 
should be added to make the mixing solution as 
thick as thin syrup. 

A piece of iron, perfectly fiat and true, is now to 
be taken, large enough to more than cover the 
inscription to be copied. Upon its surface a putty 
made of the plaster and the liquid used in mixing 
is to be spread. This should be rather stiff. The 
surface of the iron should not be too smooth as it is 
desirable that the plaster should adhere well on 
setting. The plaster should be smoothly spread to 
a depth of three-sixteenths or a quarter of an inch. 



AND THE MANIPULATION OF RUBBER. 55 

It is best applied with a palette knife or trowel, 
although a table knife will answer perfectly. If its 
surface does not become smooth it can be made so 
by applying a little of the solution with the knife 
or trowel. 

Before this has been done the model must be 
oiled. Olive oil or other clear oil is applied to all 
parts of the type faces, and the excess is then wiped 
off and cleared out of the interstices with a piece of 
blotting paper. 

Next the plate with the plaster is inverted and is 
pressed steadily down upon the model until it 
strikes the distance pieces. It is left to set. In 
about ten minutes it can be raised, when it will be 
found to give a beautiful impression true to the 
smallest detail of each letter. 

It has been said that water may be used as the 
mixing fluid. If this is done it is well to strengthen 
the mould by saturating it with an alcoholic solu- 
tion of shellac, after it has dried thoroughly, best 
for a few hours in an oven. This operates to 
strengthen the small projections that are liable to 
crumble or to break off in use. 

The dealers in rubber stamp supplies sell a lever 
press for conducting the operation of producing the 
matrix. The type is locked in a special chase, 
which is carried on a bed that travels under and out 
from under the platen of the press upon rollers. 
From each corner of the chase in which the type 
model is locked, a pin rises which is encircled by a 



56 RUBBER HAND STAMP MAKING 

spiral spring. A square frame of flat iron with 
holes at the corners for the pins to pass through, 
rests upon these springs well above the type. 
The pins pass through holes in its corners. The 
matrix plate with its coating of plaster is placed 
upon this frame, which supports it above and not 
touching the type. The whole is now rolled under 
the press and the lever pulled to produce the im- 
pression. As the pressure is released the frame 
with the matrix is raised from the type by the 
action of the springs. This can be done immedi- 
ately, and before the plaster has set. It is almost 
impossible to raise it by hand with the requisite 
steadiness. The same chase with corner pins and 
springs can be used in a screw press, the one press 
answering for making the matrix and for moulding 
and curing the stamps. The plaster matrix can 
also be made by casting from a thinner mixture of 
plaster and water. After the type has been set up, 
or the model has been selected and placed face up 
and horizontal, a little ridge or projection must be 
made all around it. Paper can be pasted around it, 
and wound with thread for this purpose. It is 
oiled and wiped off as before. The plaster is now 
mixed with water to the consistency of cream, and 
is poured upon the model until it lies even with the 
projecting ledges or paper border. In an hour or 
less it can be removed. If water is used the mould 
should before use be treated with shellac solution as 
already described. The plaster may also be mixed 



AND THE MANIPULATION OF RUBBER. 57 

with gum arabic solution, or with three to ten per 
cent, of powdered marshmallow root. This in- 
creases its toughness. 

What is known as the oxychloride of zinc cement 
appears to the author to be far preferable to com- 
mon plaster of paris. It is a trifle more expensive, 
but it costs so little that it is well worth trying. It 
is made by mixing oxide of zinc with a solution of 
zinc chloride. No particular strength of solution 
or proportions are prescribed; the zinc chloride solu- 
tion should be a strong one, and the mixture should 
be of about the consistency of soft putty. 

Zinc chloride may be bought as a solid substance 
or in strong solution. The latter answers for the 
mixing directly. It may also be simply made by 
dissolving metallic zinc in strong hydrochloric acid. 
The manipulation is exactly the same as with 
plaster of paris. 

The manufacture of papier macho and of other 
matrices is given in a special chapter. For all ordi- 
nary purposes the plaster or cement matrices are 
ample. ^ 

The stamp is made from the mixed uncured sheet 
rubber, whose preparation in the factory, including 
the operation of calendering it into sheets, has 
already been described. The best advice the reader 
can be given is not to attempt to make it except as 
a matter of interest and experiment. It can be 
purchased especially prepared for stamps from the 
dealers in india rubber. 



58 BUB 11 Eli HAND STAMP MAKING 

A piece is cut from the sheet large enough to 
cover the face of the matrix. It should have a 
perfectly smooth surface, without cloth wrapper 
marks sometimes found impressed on it. The sheet 
as received from the maker is about one-eighth of an 
inch thick. It is thrown into a box of powdered 
soapstone or talc to secure a coating of the same on 
both sides. A little is dusted over the matrix and 
the excess is blown off. The matrix is now placed 
upon the base of the press, and heat is applied. 

To carry out the process most simply the press if 
of metal may be placed upon a support over a gas 
burner or kerosene lamp, or even on a kitchen range 
or stove. It will in a few minutes become warm. 
The sheet of india rubber is now dusted off and is 
placed in the press upon the matrix. The platen of 
the press is screwed down upon it. 

As the india rubber becomes hot it begins to 
soften and flow. By the action of the screw of the 
press it must be forced down from time to time as 
it softens. This drives the putty-like material into 
all the interstices of the mould. The excess escapes 
from the sides of the tympan in cases where the 
latter is of restricted area. The press theoretically 
should bo heated to the vulcanizing temperature, 
which is 284° F. (140° 0.). In practice the heat is 
not determined with a thermometer. The operator 
learns by experience how much heat to apply. The 
regulation type of gas heated press or stamp vulcan- 
izer is shown in the illustration on page 53. 



AND THE MANIPULATION OF ItVBBER. 



59 



As some of the india rubber is sure to protrude, 
the progress of the work can be watched from its 
action. By pressing the point of a knife against it 
the period of vulcanization can be told. Before 
the material is heated it is elastic and resists the 




Oil Stove for Heating Vulcakizers. 

pressure of the knife; as heat is applied it becomes 
soft like putty; as the heat increases it again stiffens 
and becomes quite elastic. At this point the press 
can be opened and the sheet and matrix can be 
taken out or the platen swung aside. On pulling 
or stripping the sheet from the matrix it will be 
found to reproduce the model in elastic india rubber 
to the minutest detail. 

As regards the minor details there is something 



60 11UBBER HAND STAMP MAKING 

to be said. Distance pieces to gauge the thickness 
have been recommended for the home-made press, 
page 48. Cave must be taken to have these low 
enough to provide for enough excess of material to 
produce a good impression. For ordinary stamp 
work they should allow about one-sixteenth of an 
inch for the " squeeze." It will be seen that by using 
the distance or gauge pieces both for making the 
matrix and for moulding and curing the stamp, abso- 
lute parallelism of surfaces will be secured. 

The reader will have noticed in the description 
and will find at once in practice that the press has 
to be screwed up as the rubber softens. Where 
heavy iron presses are used the large mass of heated 
iron comprised in the platen of the press instantly 
heats the upper surface of the india rubber sheet and 
the heat immediately penetrates into it, while the 
heated matrix heats it from below. Thus it softens 
at once, and the press is directly turned down and 
the india rubber is driven into the mould and curing 
at once begins. But where small presses are used 
this manipulation is not so easy. For such the 
springs mentioned on page 51, are highly to be 
recommended. The matrix and india rubber can 
be put into the cold press, and the tympan with 
intervening springs can be screwed down so as to 
compress them. Then on .applying heat the mould- 
ing takes place automatically. 

With a hot press and good sheet a period of three 
to ten minutes is ample for moulding and curing. 



AND THE MANIPULATION OF HUB BEE. 61 

Instead of sprinkling with talc the matrix may be 
oiled and sprinkled with plumbago and afterwards 
polished with a brush. This is not so clean a ma- 
terial as talc and is not to be recommended for 
general use, especially as oil is a bad substance to 
bring in contact with rubber. 

The distance or gauge pieces whose use has been 
recommended are not necessary where presses work- 
ing truly parallel as regards their opposing faces are 
used. But where home-made apparatus is used 
they will be found a valuable addition. 

In describing the simple press it was said that it 
could be made of wood. It is evident that a wooden 
press could not be used for direct heating. Such a 
press must be used in a hot chamber or vulcanizer, 
properly so called. Originally rubber stamps were 
generally made in chamber vulcanizers. 

The next cut shows a combined matrix making, 
moulding and vulcanizing apparatus of very conven- 
ient and compact form and adapted for rapid work. 
As the press stands in the cut the matrix press is 
seen in front. A box or chase is carried under its 
platen by two trunnions, so as to be free to oscillate 
to a limited extent. The type model is secured in 
this box. Above this box or chase is a cross-bar 
with screw and platen attached, connected at will to 
two standards or pillars, so as to constitute the 
matrix press. 

A matrix plate swings on a hinge joint between 
the two presses. The hinge-pin is removable. Its 



02 



RUBBER HAND STAMP MAKING 



ends can be seen projecting to right and left of the 
press columns. The hinge is at such a height that 
when the matrix plate is swung forward over the 
type box it will rest upon it in a nearly horizontal 
position. The pivoted box will adjust itself so as 
to come into parallelism with the plate. 




Matrix Making, Moulding and Vulcanizing Apparatus. 

When the matrix plate is swung back it falls 
upon the base plate of the vulcanizing press seen in 
the rear. 

In use the composition used for the matrix is 
spread upon the matrix plate, which may for this 



AND THE MANIPULATION OF RUBBER. 63 

purpose be removed from the apparatus, It is 
replaced and the hinge-pin is pushed home. This 
is done with the composition coated side facing the 
front of the apparatus as it stands in the cut. The 
plate is then swung forwards, the platen of the 
matrix press being turned forward out of the way, anc 
is pressed down upon the type or other model that 
rests in the type box. If desired the press is used 
to force it home. The cross-bars of both the presses 
are arranged to swing each one on one of the 
pillars, so that the platens are turned to one side out 
of the way of the matrix plate as it is swung back 
and forth. 

The pressure is released and the platens are 
turned aside. The matrix plate is swung over to 
the rear upon the bed-plate of the vulcanizing 
press. Here it lies with the composition-matrix 
upwards. 

A lighted lamp, either alcohol or gas, is placed 
beneath the bed-plate of the vulcanizing press on 
which the matrix rests. This quickly dries it and 
brings it to a good curing temperature. The cross- 
bar and platen may be swung oyer it during the 
heating so as to be heated at the same time. The 
matrix is talced when dry and hot; the mixed sheet 
itself talced, is placed upon the matrix, the platen 
is screwed down upon it, and in a minute or two 
the moulding and curing is completed. 

A vnlcanizer, properly speaking, is a vessel ar- 
ranged to heat to a definite degree any desired arti- 



64 RUBBEli HAND STAMP MAKING 



Rubber Stamp Vulcanizes. 



cies which are to be cured. The favorite type have 
been the steam vulcanizers. If steam is generated 
from water at a constant pressure, other things 



AND THE MANIPULATION OF RUBBER. 65 

being equal a constant temperature will be pro- 
duced. By raising or lowering the pressure the 
temperature can be made to rise or fall. A steam 
vulcanizer is a tightly sealed vessel whicli contains 
water and which is provided with a thermometer or 
a pressure gauge as well as a safety-valve, safety 
disc or safety plug. By keeping the gauge at con- 
stant pressure or by keeping the thermometer con- 
stant the temperature can be limited and kept 
steady. The following table gives some pressure in 
pounds per square inch with temperatures corre- 
sponding to steam of such pressures: 



. per square 


inch. 


Temp. Fahr. 


Temp. Cent. 


45.512 




275° 


135° 


52.548 




284° 


140° 


60.442 




293° 


145° 


67.408 




300.2° 


149° 



The illustration, p. 64, shows a vulcanizer of modern 
type made for rubber stamp work. In some recent 
vulcanizers the water and steam are excluded from 
the vulcanizing chamber, being contained within 
double walls forming a steam jacket and maintain- 
ing a constant heat within the chamber. These 
illustrate a point that has been much misappre- 
hended, namely that curing is independent of pres- 
sure or atmosphere. Because vulcanizers have 
generally been filled witli steam at high pressure 
many have supposed that the steam or pressure had 
something to do with their action. The fact is that 



66 



RUBBER HAND STAMP MAKING 



it is only the heat due to the steam at such pressure- 
that is instrumental. Steam is a very powerful 
radiator and absorber of so called radiant heat. For 
this reason an atmosphere of steam maintains all 




Steam Jacket Vttlcanizeb. 

parts of the vulcanizer at an even temperature and 
is to that extent advantageous. Its presence and 
tne pressure it generates are not by any means re- 
quired for vulcanizing. Its pressure is entirely 
without effect. 

To use a steam vulcanizer. water is introduced.. 



AND THE MANIPULATION OF RUBBER. 67 

the article in the press or mould is placed in it, and 
the top is secured. Heat is then applied, best if on 
the small scale, from a Bunsen gas burner gas, or oil 
stove. Either the pressure gauge or thermometer 
may be watched, and the flame turned up or down 
to keep it at the proper temperature. 

Moulding cannot be executed in the ordinary 
closed chambers. The press must first be heated to 
the temperature of boiling water or thereabouts and 
the moulding is then effected by screwing down the 
mould screw, upon the sheet and matrix. It is 
then placed in the vulcanizer and cured. 

The manufacturers supply gas regulators which 
automatically regulate the gas supply. These are 
worked by the steam pressure. If any one wishes 
to study the practical manipulation of small steam 
vulcanizers he can see them in use at any dentist's 
office. 

There is no need of a steam vulcanizer for ordi- 
nary stamp work. The hot press system already de- 
scribed answers every purpose and is in use by the 
most advanced manufacturers for thin sheet work. 
But if a wooden moulding press is used then it must 
be heated in a vulcanizer or some kind of oven or 
hot chamber. 

A very simple and reasonably satisfactory oven or 
air bath can be made from a flower pot and a couple 
of tin plates. A plate larger in diameter than the 
mouth of the flower pot forms the base of tho ap- 
paratus. This is supported on a stand over the gas 



G8 



RUBBER HAND STAMP MAKING 



lamp or other source of heat. A smokeless flame or 
one depositing no lampblack should be used. Alco- 
hol or a kerosene oil stove illustrated on page 59 are 
excellent. On this plate a smaller plate is inverted, 
which latter must be so small as to be surrounded 
by the flower pot and to be included within it when 
the pot is placed over it like an extinguisher. 




Flower Pot Vulcanizek on Stand. 

A chemical or round stemmed thermometer is 
arranged to go through the aperture in the up- 
turned bottom of the pot. This may be hung from 
a support or it may be secured by passing through 
a hole in a cork or block of wood. Its bulb should 



AND THE MANIPULATION OF BUB BE R. 69 

be near the part of the chamber to be occupied by 
the mould or press. 

The press with the article to be cured is placed 
upon the inner plate. The temperature is main- 
tained at the proper point by regulating the heat, 
and all the conditions for excellent work are sup- 
plied. The disposition of the apparatus is shown in 
the cuts. 




Interior of Flower Pot Vvlcanizer. 

Another arrangement equally simple is given in 
the next cut. An iron kettle has a layer of type 
metal or lead poured an inch thick cast within it 
upon its bottom. A thermometer passing through 
a hole in the cover enters a cup of glycerine that 
stands upon the bottom. This gives the tempera- 
ture. 

The object of having a thick or a double bottom 
is to prevent excessive radiation of heat from any 
one part. The essential condition for good opera- 



70 



RUBBER HAND STAMP MAKING 



tion is to maintain an even temperature throughout 
the chamber. 




Fish Kettle Vulcanizer. 



The thermometer is not an absolute necessity. 
By removing the press from time to time and in- 
specting the overflow of india rubber the progress 
of the operation can be watched. An extra piece 
of india rubber may be placed on a piece of wood 
by the side of or upon the wooden portion of the 
press, and its condition can be taken as the crite- 
rion. Pressure with the point of a knife will tell 
the vulcanizing point. 

By the press system .of curing, a heat far above 
the vulcanizing temperature may be made to do 
good work by a very short application. There is 



AND THE MANIPULATION OF HUB BEE. 71 

however danger of burning the work if left in too 
long. If the air-bath with thermometer or the 
steam vulcanizer is used, and the heat is kept down 
to the proper curing temperature, there is no danger 
of burning the india rubber even if the curing is 
considerably prolonged. 

As the flower pot has often to be lifted off for 
introduction or removal of the press, and as it gets 
quite hot, a holder of some kind is requisite. A 
piece of heavy blotting paper is very convenient for 
this purpose. 

The flower pot system with thermometer can be 
further simplified by being used on a stove or range. 
A china saucer inverted, or some similar support, 
should be placed under the pot. A part of the 
stove at very low heat will suffice. The kettle vul- 
canizer, can also be placed on a stove so as to dis- 
pense with gas or oil. 

Finally ; as the last step in simplifying the work, a 
stamp can be made without any special apparatus 
beyond a hot flat iron. The matrix may be placed 
on a stove where the heat is rather low, the talc- 
coated mixed rubber sheet placed upon it, and on 
this a hot flat iron. In a few minutes if the heat is 
sufficient the stamp will be finished. 

A few words may be said about the type. High 
spaces and quads between the letters should be used, 
such as will come up to the shoulder of the type, as 
has been said. But a very nice effect is produced 
by using low quads between words. This leaves 



72 RUBBER HAND STAMP MAKING. 

each word elevated by itself, producing a good 
appearance. 

Autograph stamps are made from a model cut in 
wood by a wood engraver. The autograph is writ- 
ten in some form of copying ink upon a piece of 
paper, and is transferred by moistening and. pres- 
sure to a block of wood. With an engraver's tool 
the wood is cut away from the lines, as the block is 
routed after the inscription has been "outlined." 
The woodcut is used as a model for making a 
matrix. 

It is evident that an autograph of fair quality 
could be obtained from a chalk plate. But in rub- 
ber stamp work to get good results certain essential 
parts should be of the best. These parts include 
the mixed rubber, model and matrix. A departure 
from excellence in any of these tends to the produc- 
tion of an inferior stamp. What is known as a 
"healthy cure" is above all essential to the appear- 
ance of the product. 

The stamp thus made is attached to a wooden 
handle by common glue or by one of the rubber 
cements given in chapter XVI. 



CHAPTER VI. 

INDIA RUBBER TYPE MAKING. 

India rubber type are often used to set up differ- 
ent inscriptions in wooden handles, or different date 
figures in rubber stamps. The latter are in such 
cases made with slots or recesses to receive them. 
Rubber type are much shorter than regular type, 
and as a rule are larger in the body in proportion to 
the face of the letter. Where only a few are re- 
quired the following process is the simplest way of 
making them from mixed rubber sheet. 

The type which are to be copied are set up on a 
level base or imposing stone, and quads or spaces 
are put between them. High quads and spaces 
should be used; otherwise they should be pushed up 
until even with the shoulders of the type. After 
oiling the faces a matrix is produced exactly as 
described for stamps. Before it has set quite hard 
the plaster or cement is cut off so that it will just fit 
within a little " flask" or frame. 

The latter may be made of tin or wood and may 
be rectangular or circular, provided it is large 
enough to include within its area the full working 
face of the matrix. It should be about half an inch 



74 



RUBBER HAND STAMP MAKING 



or five-eighths of an inch deep. Its object is to pre- 
vent the softened india rubber from spreading, so 
as to secure the requisite height of the type pro- 
duced. 

A piece of wood or metal is cut so as to fit closely 
within this frame like a plunger. It is provided 
with shoulders or cross pieces, so as to limit the 
depth to which it can be inserted. It will be seen 
that when matrix, flask, and plunger are all put 
together a complete mould for a block of type is 



■1. 



India Rubber Type Mould. 

produced, as shown in the illustration, the matrix 
with its plate forming the bottom of the box. 
After the flask is placed upon the matrix it is filled 
with the mixed uncured india rubber sheet. As a 
matter of preference thick sheet is used, but scraps 
of all shapes can be employed as it all fuses to- 
gether. The mould and matrix are of course first 
well dusted with talc powder. The plunger is put 
on and the whole is pressed. Heat is next applied 
in a vulcanizer or hot air chamber, such as the 
flower pot arrangement, or in boiling water. As the 
sheet reaches the boiling point 212° F. (100° C.) the 
flask is removed and the plunger examined. If it 



A ND THE MA NIP ULA TION OF K UBBER. 75 

goes down to its seat without expelling any india 
rubber more of the latter is required and is accord- 
ingly inserted, the plunger being taken off for the 
purpose. The softened gum should ooze out around 
the sides of the plunger. The whole is again put 
under pressure, and the platen is screwed down, and 
if all is right an excess of rubber showing itself, the 
whole is put in the hot chamber, the heat is raised 
to 284° F. (140° C), and is maintained there for 
half an hour. 

It is almost a necessity to secure the matrix plate 
to the bottom of the flask. This for a single opera- 
tion may be done by screws, or ior several operations 
by hooks or catches. 

When the curing is complete the mould is re- 
moved from the vulcanizer, is allowed to cool and is 
opened. The block of type will come out with per- 
fect reproduction of the letters upon one side. If 
all the directions have been followed as regards dis- 
tance pieces, level imposing surface, etc., both faces 
will be exactly parallel, and any number of other 
blocks can be reproduced of exactly the same 
height, not necessarily from the same matrix, 
although one good matrix can be used many times. 

The type have now to be cut apart. This is done 
with a sharp knife which is kept wet. It is worked 
with a sawing motion, and if sharp and properly 
used will cut with regularity, and smoothly. Type 
with knife marks on the sides are always unmechan- 
ical in appearance and seem to be " home made/' 



76 RUBBER HAND STAMP MAKING. 

The object of using high quads and spaces or of 
pushing them up, will now be evident. It secures 
the evenness of the general face of the block of 
letters, which otherwise would have a deep depres- 
sion between each pair of letters. If the quads and 
leads are properly arranged, the letters will project 
upwards from a smooth, plane surface. 

The dealers in rubber stamp maker's supplies sell 
special steel moulds for the purpose of making 
them. This does away with all necessity for making 
matrices, and making up a flask, etc. The general 
manipulation is that given above. Where many are 
to be made the regular mould is by all means to be 
recommended. 

Sometimes type are made by cementing single 
letters made by the stamp process upon wooden 
bodies. 



CHAPTER VII. 

THE MAKING OF STAMPS AND TYPE FROM VULCAN- 
IZED INDIA RUBBER. 

Although all reference hitherto in the matters of 
stamps and type has been to their manufacture from 
uncured india rubber, a good deal can be done with 
vulcanized and cured gum. The stock that is 
known in the trade as pure gum, such as is used for 
bicycle tyres, for steam packing and the like, can 
be made to yield to moulding to a certain degree. 
It will not flow and unite as will the uncured gum, 
but it is evident that in certain cases its stiffness is 
even an advantage. Thus with it, rubber type can 
be made without any flask or frame. The material 
has stiffness enough to support itself. 

The manipulation is of the simplest. A piece is 
cut out with a knife so as to be of proper thickness 
and size. It should be a little thicker than will 
ultimately be required. The two opposite surfaces 
should be smooth and parallel. It is talced, and 
placed in the press with the matrix beneath it, and 
subjected to pressure by the screws being turned 
down. It is then placed in the vulcanizing 
chamber and heated to about 284° F. (140° C). 



78 RUBBER HAND STAMP MAKING 

After it has become hot it softens a little. The 
press is removed from the hot chamber and is again 
screwed down as hard as the matrix can stand. 
This point is largely a matter of judgment. The 
heat is largely indifferent as long as it is anywhere 
near the above temperature. 

By one or two repetitions of the pressing and 
heating the softened india rubber can be made to 
take quite a deep impression from a suitable matrix. 
It is allowed to cool under full pressure. When 
removed from the press, it will retain the characters. 

It is evident that impressions in as high relief or 
as deep and clear as those yielded by uncured india 
rubber need not be expected. But where the other 
cannot be had, or where some experimental or tem- 
porary work only is on hand, this process will be 
very convenient. 

The material may be half an inch thick. From 
such india rubber type can be cut with advantage. 

Old rubber can be thus used. The writer has ob- 
tained excellent results from pieces of an old dis- 
carded bicycle tyre. 

The great point is to apply a heavy pressure to 
the hot material. Many other articles can be thus 
produced extemporaneously. At the same time it 
must be considered only a makeshift. One who has 
used the soft, easy flowing uncured gum would 
never be reconciled to the use of so rigid and diffi- 
cultly moulded a material, one too that can never 
be trusted to reproduce intricate moulds of consid- 



AND THE MANIPULATION OF RUBBER. 79 

erable depth. In the slow yielding of the half 
melted unc tired gum, so amenable to slight pressure, 
a quality of availability is found that is missed in 
the other. One is worked by main force where the 
other readily yields and takes the most complicated 
shapes. 

By the above process stamps of such thickness 
may be made that they can be used without handles. 
It is also useful for impressing a designation of any 
kind upon ready cured articles. It suggests a very 
useful department of manipulation of India rubber. 

The heating and moulding can be done also in a 
hot liquid bath such as described in chapter XI. 



CHAPTER VIII. 

VARIOUS TYPE MATRICES FOR RUBBER STAMPS AND 

TYPES. 

Matrices for stamp moulds can be made by sev- 
eral of the methods used by stereotypers. Thus an 
electrotype could be taken directly from the face of 
the type. There would be little or no utility in 
doing this where the simpler processes are available. 

PAPIER MACHE MATRICES. 

The stereotyper for daily newspaper work uses 
very generally the papier mache or " flong" process 
of reproducing the page. This is also available for 
rubber stamp making. 

The first requirement is paste. This is made by 
softening twelve parts of whiting in forty parts of 
water, letting it soak for an hour or more. Nine 
parts of wheat flour are added. This is best mixed 
with a little water before adding to the main mix- 
ture. It is then brought to the boil and seven parts 
of glue softened by soaking in twenty-one parts of 
water, are added. For each gallon of such mixture, 
one ounce of white crystallized carbolic acid is 
added if it is to be kept for a long time. 



A ND THE MAN IP ULA TION OF B UBBEB. 8 1 

The "'flong "is made by pasting together, one 
on top of the other, a sheet of fine hard tissue 
paper, three sheets of blotting paper (about 23 
pounds to the ream), and a heavy sheet of manilla 
paper. The pasting must be smooth and each 
layer must be pressed and rubbed down, but not too 
hard. It is very important to secure perfect 
smoothness and regularity, and entire absence of 
air bubbles. 

Every printing office where the process is used 
has its own traditions as to the preparation of flong. 
As a great deal depends on manipulation, it would 
be well to endeavor to inspect its practical use in a 
newspaper printing office before making it. Ready 
prepared flong can also be procured. 

The form of type must be very clean and there 
must be no paste on the tissue paper face of the 
flong. The type are lightly oiled, some powdered 
talc is dusted over the damp tissue paper face of 
the flong, and the mass is laid face downward on 
the type. With a stiff haired brush the paper is 
now beaten down against the type. Great care 
must be taken to beat vertically; a slight side action 
will ruin the resulting matrix. If the brown paper 
will not stand the beating, a cloth may be spread 
over it. 

The progress of the work can be watched by rais- 
ing up a corner from time to time. When suffi- 
ciently deep the last touch is given by the printer's 
planer. This is a block of hard wood. It is placed 



82 RUBBER HAND STAMP MAKING 

upon the back of the flong and is hammered down. 
The operation is repeated until the entire area has 
been treated. For much rubber stamp work the 
area would be so restricted that shifting would be 
unnecessary. 

The work is then put into a heated screw press, 
such as the vulcanizing and matrix press, and is 
dried for a period varying from some minutes up to 
half an hour. Some blotting paper is advanta- 
geously pressed on top of the whole in the press 
while drying. The press is opened, the flong re- 
moved, and dried in an oven. It is kept under a 
piece of wire net while drying to keep it flat. The 
net may be of wire, .064 inch thick, with six 
meshes to the inch. This baking is not strictly 
necessary for rubber stamp work. 

This gives a matrix which may be used as rub- 
ber stamp moulds. In use it is recomended to 
place a piece of smooth tin foil over it. This tends 
to give a smoother surface to the rubber. 

STRUCK UP MATRICES. 

Didot's polytype process may be advantageously 
used for producing type metal matrices. The fol- 
lowing is the method of applying it. 

The type form is firmly locked and is backed up 
by and secured to a solid block of wood. It is sus- 
pended in a sort of gallows frame with the face of 
the type downward and exactly level a few inches 
above a table. Underneath it a shallow tray is 



AND THE MANIPULATION OF RUBBER- 83 

placed, into which some melted type metal is 
poured. The melted metal is carefully watched. 
The block and type are held by a catch so as to be 
released at will. Just as the type metal is on the 
point of solidifying, the block is released and drops 
upon the metal in the tray. The type should be 
slightly oiled. The force of the blow produces a 
matrix in the metal, and the form can at once be 
removed. 

It is well to have accurately adjusted distance 
pieces for corresponding striking pieces on the type 
block to impinge upon. The process is highly 
spoken of, especially for small forms such as those 
mostly required for rubber stamps. 

CHALK PLATES. 

The base for this form of matrix is a metal 
plate whose surface is slightly roughened with sand- 
paper. It is next rubbed over with white of egg, 
and flooded with the chalk wash made as follows: 
Flong paste (described under Papier Alache Ma- 
trices, page 80), six ounces; whiting, twenty-four 
ounces; water, three pints. The whiting is softened 
by soaking for an hour or more. The whole must 
be intimately mixed. It should cover the plate to 
the depth of one-thirtieth to one-twentieth of an 
inch. The plate is dried in a perfectly horizontal 
position. 

When dry the design or writing, etc., is made 
with a smooth steel point, the lines being carried 



84 RUBBER HAND STAMP MAKING. 

clear through the white layer to the metal. The 
mould is now baked at a temperature well above 
boiling water; as high as 392° F. (200° 0.) may be 
reached without harm. 

If the coating seems too thin, an extra coat can 
be given between the lines especially over the larger 
areas. This must be done before the baking. A 
pipette may be used for putting on this coat. This 
deepening has the bad effect of increasing the 
chance of the coating stripping from the metal. 

The matrix thus prepared is used in the press 
just as is the ordinary plaster matrix. It is suited 
for reproduction of autographs, scrip, diagrams, 
etc. 



CHAPTER IX. 

THE MAKING OF VARIOUS SMALL ARTICLES OF INDIA 

RUBBER. 

India rubber can be so readily shaped in moulds 
and the latter are so readily made of plaster of paris 
that any one who is interested in such things will 
find endless amusement in working out different 
designs. Before suggesting any specific articles 
the following are the general points to be kept in 
mind. 

The material may be uncured mixed sheet of any 
thickness. As we have seen this material when 
heated and pressed runs together. It can be forced 
into any shape by comparatively slight pressure. 
80 exactly does it reproduce the smallest line or 
mark, that care must be taken to have the moulds 
very smooth and free from defect. Powdered soap- 
stone is used to prevent adherence to the mould, but 
great care must be taken not to mix it among the 
pieces of the india rubber, where several are used 
in one article, as it will prevent their coalescing 
or running together. 

Another point is to contrive to introduce the 
proper quantity of rubber. The aim must be to 



86 RUBBER HAND STAMP MAKING 

have a slight excess, but to avoid waste this should 
be as little as possible. Unless some rubber is 
squeezed out there is no certainty that the mould 
has been filled. Any projecting "fins" from the 
overflow are cut off with a knife or scissors after the 
article is removed from the mould. 

Plaster of paris or dental plaster mixed with dex- 
trine or gum arabic water or the zinc oxvchloride 
cement, already described, is to be recommended for 
the moulds. They should be made, if deep, in 
frames or " flasks " of tin, as plaster if unsupported 
is liable to split open when the rubber is forced home. 

For many articles the hot press can be used. 
Such articles are mats and other thin flat pieces. 
The rubber stamp sheet is a good material for them. 
For thicker articles a thicker sheet can be used, and 
sheet of any gauge can be procured from the maker. 
Much of what has been said about india rubber type 
applies to the making of miscellaneous shapes. It 
will also be understood where wooden moulds are 
spoken of that plaster, or, still better, metal can be 
substituted, and is to be recommended for nice 
work as the grain of the wood is very apt to show 
where the india rubber comes in contact with it. 

Suction discs and similar small articles into which 
an extra thickness of india rubber enters are best 
cured in a vulcanizer. The flower pot arrangement 
is excellent for such. The time for curing may 
be somewhat extended on account of the greater 
thickness of material to be acted on. 



AND THE MANIPULATION OF RUBBER. 87 

Suction Discs. — For suction discs a mould is 
required which will produce a shallow cup with the 
edge feathered or reduced to a very slight thickness. 
Its outer surface should be raised in the centre so 
as to give a projection for attachment of the hook. 
The discs are generally made small, not over an inch 
in diameter, as they are not reliable for any heavy 
service. Their principal use is to suspend advertis- 
ing cards and light articles to the glass of show 
windows. The following is a method of making a 
simple mould. 

A hole to give the outside contour should be 
bored in a small piece of wood. A marble which 
will exactly fit the hole is next required. Some 
plaster of paris is mixed with water and put into the 
bottom of the hole, and the oiled marble is pressed 
down until the plaster rises and fills the entire space 
under the marble. After it has set the marble is 
removed. The proportions should be so arranged 
that the plaster will have risen at the sides within 
an eighth of an inch of the surface of the wood. 
This gives the exterior mould. For the cup or 
hollow a marble a shade too large to enter the 
hole may be used. 

One or if necessary two thicknesses of mixed 
sheet rubber cut into disc shape so as to fit the 
hole are inserted in the block, and the larger marble 
is placed on top and screwed down by the press. 
Heat is now applied in the vulcanizer. When the 
thermometer indicates 212° F. (100° C), or better a 



88 



RUBBER HAND STAMP MAKING 



little more, the mould is withdrawn and the screws 
turned until the rubber is forced down and the 
excess begins to squeeze out between the marble and 
the wood, which two should now nearly touch. It is 
replaced and the heat is brought up to the curing 
temperature .284° h\ (140° C). It is possible that 
a second screwing up may be needed. The spring 
press is in such cases particularly convenient as it 
avoids the necessity for re- 
moving the press from the 
vulcanizing chamber. After 
half an hour it will be thor- 
oughly cured. A hole is 
made through its centre from 
side to side thereof, but not 
penetrating the disc, and 
through this hole a brass 
nail is thrust and bent into 
hook form. 

In the cut the correct shape for the mould and 
consequently for a suction disc is shown. This can 
be easily secured where a disc already made is procur- 
able by casting in plaster, or, with a little ingenuity 
the template for the mould and the plunger to be 
used instead of the marble can be whittled out of 
wood. The lower body of the mould in such a case 
can be made of plaster of paris. To secure the 
alignment of the two parts of the mould, dowel pins, 
indicated in dotted lines, should be placed near the 
periphery. The gum should be introduced in a lump 




Mori-D for Suction Discs. 



AND THE MANIPULATION OF RUBBER. 89 

near the centre, in order that it may sink well down- 
wards to the bottom of the mould before spreading 
laterally. Sometimes the tips have a recessed 
end. This is secured by the use of a mandrel, 
shown in dotted lines in the axis of the mould. 
Such discs are sometimes made to be cemented to 
arrows to be discharged against smooth surfaced 
targets, to which they adhere on impact by atmos- 
pheric pressure, giving rise to a very interesting 
game. 

Another use of suction discs is as photographic 
negative holders. They can be fastened to a wooden 
handle and be attached by suction to the back of 
a negative under treatment. For this purpose they 
should be at least two inches in diameter. 

Pencil Tips. — These are generally little cylinders 
of india rubber, which fit into a tube that slides 
over the end of the pencil. They can be thus sim- 
ply made. A hole is bored in a piece of wood the 
diameter of and a little more than the depth of 
the pencil tip. A short cylinder that exactly fits 
the hole is required for plunger. The gum is put 
into the hole in little discs, or rolled up into a 
cylinder, the plunger is placed on top, and the 
mould put in the press. It is shaped by pressure 
and cured as described. 

Sometimes the tips are cup shaped. For these 
the mould is made in two sections fastened by 
catches or by pins set in the plaster as shown in the 
cut. The hole is made larger at bottom than at 



90 



RUBBER HAND STAMP MAKING 



top, and at the top is a little smaller than the shaft 
of the pencil. A plunger that nearly fits the small 
end is provided. The india rubber is placed in the 
mould and heated. When soft, the plunger is 
forced down to the proper distance in the press 
and the article is cured. Care must be taken to 




Mould for Pencil Tips. 



give the plunger a good coating of talc, and it must 
be made to sit vertically. The arrangement of a 
cylindrical hole shown in the cut secures this result 
perfectly. As distance piece a pin is passed through 
the plunger. 

Cane and Chair Leg Ttys, etc. — By carrying out 
the process just described with larger moulds and of 
slightly different section very convenient tips for 
chair legs and walking canes can be made. Such 
tips can be modified in size and thickness to answer 
as covers for the mouths of bottles, test-tubes, etc. 

Corks. — These may be made in moulds tapering 



AND THE MANIPULATION OF RUBBER. 91 

from top to bottom. The india rubber must be 
packed in with great care to secure as solid filling as 
possible. A plunger is used that enters the larger 
end and is a very little smaller in diameter, so as to 
descend a little way into the mould. This distance 
determines the length of the cork. As the perim- 
eter of the plunger strikes the walls of the mould 
it cuts off almost completely the excess of rubber 




Mould for Rubber Corks. 



that has squeezed up past it. An excellent modifi- 
cation of the mould is shown in the cut. The 
upper part with parallel sides serves as a guide for 
the plunger. It is a similar extension as the one 
recommended to be used for the plunger in the hol- 
low pencil and chair leg tip moulds just spoken of. 

Mats. — These may generally be made in the hot 
press. Designs for them in great variety may be 
found in cut glass and pressed glass dishes. Many 



X 



92 RUBBER HAND STAMP MAKING 

of these have patterns on their bottoms that can be 
moulded in plaster to serve as matrices. 

Cord, Thread and Seamless Tube. — By placing the 
mixed india rubber in a cylindrical mould fitted 
with piston and with one or more round holes in the 
bottom, the material may be softened by heat and 
forced out of the holes by depressing the piston. 
This will form cylindrical thread or cord. As it 
descends it may be received in a box of powdered 
talc and be afterwards cured. By providing the 
hole with a mandrel seamless tubing may be thus 
made. In making such the mandrel usually re- 
mains in place during the curing. Plenty of 
powdered talc must be used. 

Skeletonized Leaves as Models. — These would form 
interesting models from which matrices could be 
made in plaster. It would be possible to produce 
some very pretty stamps or mats from these and 
similar models. 

After some experience inspection of any article 
will show how it was moulded. The fin will indi- 
cate the joint in the mould, and with this as a clew 
the mould can be almost certainly constructed like 
the original. 

India Ruhbw Bulbs. — Bulbs and hollow articles 
generally, such as dolls, toys and the like, cannot 
be made without special high pressure hollow 
moulds. The general process consists in cutting 
out gores from mixed sheet as for a balloon. The 
edges are coated with cement (thick benzole or ear- 



AND THE MANIPULATION OF RUBBER. 93 

bon disulphide india rubber solution) and while 
the rubber is warm the seams are pressed and 
knitted together with the fingers. A hole is left in 
one place through which some pure water or water 
of ammonia is introduced. The bulb is now blown 
up with the mouth or otherwise, and while inflated 
the hole is pressed shut. This is often done with 
the teeth. Any projections around the seams are 
cut off with curved scissors. The mould is of iron 
and in two halves. Powdered talc is applied, and 
the bulb is placed in and shut up in the mould 
which it should exactly fill. The mould is clamped 
together and the whole is put into a vulcanizer, and 
the rubber is cured. The steam and vapor formed 
by its liquid contents expand it and press it with 
great force against the sides of the mould. After 
curing the mould and bulb are removed from the 
vulcanizer, cooled by a shower bath of cold water, 
the mould is opened and the bulb is removed. Often 
an iron pin is left projecting through the side during 
the vulcanizing, which pin, when withdrawn, leaves 
the necessary aperture, or it is perforated. The bulbs 
are polished by tumbling in a revolving cylinder. 
Considerable skill and practice are needed to succeed 
in making hollow bulbs. Great accuracy is needed 
in cutting out the gores and in joining the seams. 



CHAPTER X. 

THE MANIPULATION OF MASTICATED SHEET KUBBER. 

The manipulation of pure sheet rubber is simple, 
yet is liable to lead to disappointment. When two 
pieces are laid face to face and cut across with a 
sharp knife, or scissors, the edges will adhere with 
considerable tenacity. This may be increased by 
applying some thick solution of india rubber in a 
volatile solvent, and by manipulating the sheets so 
as to bring the entire surfaces of the cuts together. 
Finally the material may be charged with sulphur 
by absorption or by Parkes* process, and cured in 
a glycerine or calcium chloride bath, all of which 
are described in chapter XI. The same treat- 
ment will affect the cement used in making 
the joint also, bringing about its vulcaniza- 
tion. 

Such in a few words is the main process in the 
treatment of this class of goods. Where it is de- 
sired to prevent adherence, soapy water or powdered 
talc is used. 

Adherence may be produced between the surfaces 
of the sheets if they are clean, by pressure and a 
little warmth. The method of making toy balloons 



THE MAN IP ULA HON OF B UBBEB. 95 

will give an example of how the article is dealt with 
by the manufacturer. 

A pile of pieces of masticated sheet rubber is 
made. Every piece has one side coated with pow- 
dered talc, and two talc-coated sides are placed in 
contact in each pair. As they are piled up, the 
outer surfaces of each pair are moistened with 
water. A steel punch or die, pear shaped in out- 
line, is used to cut down through the pile, cutting 
all the pieces into that shape. 

The pile is then taken apart in pairs. The separa- 
tion takes place between the wet surfaces, the edges 
of each pair adhering slightly so as to enclose the 
talc-coated surfaces. The neck is opened if neces- 
sary. A rather weak or thin solution of india rub- 
ber in benzole is now brushed over the freshly cut 
edges. By pulling out the centre of each piece the 
edges are brought into contact, and adherence is 
produced. 

If the Parkes process of vulcanizing, chapter XL, 
is employed they are cured to the slight extent nec- 
essary upon a tray coated with talc. The balloons 
are then ready for inflation. 

They are rather delicate articles to make except 
for immediate use as the thin material is liable to 
become over vulcanized. 

In the chemical laboratory sheet rubber can be 
used for covering the ends of glass stirring rods. 
These answer very nicely for cleaning out from 
beakers the last particles of a precipitate. The 



96 RUBBER HAND STAMP MAKING. 

sheet is cut of proper size and is bent around the 
end of the rod and cut off close with a pair of scis- 
sors. It adheres where cut. It is then pinched 
with the fingers to bring the edges into better con- 
tact and the operation is complete. A slight heat 
makes it adhere better. 

To connect glass tubes in setting up laboratory- 
apparatus the same material was formerly used. It 
was wrapped around the joint, tied with thread and 
slightly warmed. At present this form of connec- 
tion is wholly displaced by ready made rubber 
tubing. 

It is interesting to observe in all articles made 
from this sheet the marks of the original cutting 
knife. These may be observed in inflated balloons, 
as parallel lines running all over the surface, and 
magnified by the expansion due to the inflation. 



CHAPTER XL 

VARIOUS VULCANIZING AND CURING METHODS. 

The regular methods of vulcanizing and curing 
can be departed from and good results obtained. 
A few excellent methods differing essentially from 
the ordinary ones are described which will be of 
service to workers on the small scale, as they enable 
one to dispense with vulcanizer and air bath en- 
tirely. 

One type of curing process does away with the air 
or steam vulcanizer, and substitutes, as the curing 
agency, a hot bath of liquid. For this purpose a 
fluid is required that will not act injuriously upon 
the india rubber, and which will give a curing 
temperature without boiling away. One favorite 
liquid is glycerine. This can be heated to the nec- 
essary degree and is an excellent substitute for the 
expensive apparatus often used. For experimental 
work it is exceedingly convenient. 

In use it is placed in a vessel of proper size 
and a thermometer is suspended so that its bulb 
dips into the liquid near one side and does not 
touch the bottom of the vessel. The heat is applied 
by a gas burner, alcohol lamp or oil stove. Of 



98 RUBBER HAND STAMP MAKING 

course the vessel may be placed on an ordinary 
cooking stove or range, and the heat may be gradu- 
ated and adjusted by moving it about until it 
reaches a part of the stove where the proper heat 
will be maintained. 

The mould with its contents is immersed in the 
glycerine, care being taken to see that it so placed 
as to assume the mean temperature of the liquid 
and not to be heated too hot. This might happen 
if it stood on the bottom of the vessel, so it is well 
to have it supported or suspended a little above 
it. 

It is easy to see that the whole may be so arranged 
that the screw handle or pressure nuts of the mould 
will rise above the liquid. In this case the press 
can be screwed down while the article is heating. 

Instead of glycerine a strong solution of some 
salt in water has been recommended. A solution 
of calcium chloride, or some other salt can be sub- 
stituted. Either are very cheap and will be quite 
satisfactory. 

Another treatment which applies also to the mixing 
operation is by the sulphur bath. Sulphur is melted 
in an iron vessel and brought to a temperature of 
248° F. (120° C). A piece of unmixed pure caout- 
chouc immersed in this bath will gradually absorb 
sulphur. The case is almost parallel with the 
absorption of water or benzole by the gum. The 
piece swells and thickens as it is acted on and 
eventually will contain enough sulphur for vulcani- 



AND THE MANIPULATION OF RUBBER. 99 

zatioa. It may absorb as much as fifty per cent. 
The point of proper absorption must be settled 
more or less empirically or by successive trials. 

After enough has been taken up the piece is re- 
moved and dipped into cold water, which cracks the 
adherent sulphur so that it can be brushed or rubbed 
off. This gives a piece of mixed rubber ready for 
moulding and curing. It can be heated and 
moulded and may be cured as desired, in a liquid 
bath, hot press or vulcanizer. 

It will be observed that this provides for the ad- 
mixture of sulphur only; no talc or other solid can 
be thus introduced. The addition of these solids 
tends to make the rubber of a more attractive color 
and their use is not to be deprecated in all cases. 
Hence the sulphur bath process is not to be consid- 
ered a perfect one. 

In the sulphur bath the mixing and curing 
processes can be combined. If the liquid sulphur is 
heated to the vulcanizing temperature, 284° F. 
(140° C), a thin strip of gum immersed in it will 
be vulcanized completely in a few minutes. A 
heating of several hours at the lower temperature 
will effect the same result. 

The sulphur bath processes must be regarded as 
unsatisfactory. It is not easy to feel that any de- 
pendence can be placed upon them as regards re- 
liability or constancy of product. The sulphur also 
will mostly effect the surface. Thin pieces may be 
satisfactorily treated, but the same confidence can- 



100 RUBBER HAND STAMP MAKING 

not be felt as is experienced when specific amounts 
of ingredients have been mixed in with pure caout- 
chouc in a regular mixing machine. 

The sulphur bath is of value to the experimenter, 
enabling him to do his own mixing without expen- 
sive apparatus. 

Bromine, iodine, chlorine and nitric acid are vul- 
canizers. A piece of sheet rubber dipped into 
liquid bromine is instantly vulcanized. Iodine and 
nitric acid have also been used in commercial 
work. 

Alkaline or alkaline earth sulphides can be em- 
ployed in solution under pressure for vulcanizing. 
At a vulcanizing temperature their solutions will 
answer for thin sheet very well. Polysulphides of 
calcium have thus been employed. 

By simply lying embedded in finely divided sul- 
phur at a temperature of 233° F. (112° C.) as much 
as ten per cent, of sulphur may be absorbed by thin 
sheet rubber. This is one of the processes pecu- 
liarly suited for work on the small scale. It may be 
used instead of the Parkes process next to be de- 
scribed. 

Chloride of sulphur is an orange red mobile 
liquid of a peculiar and disagreeable odor. It boils 
at 276° F. (136° C.). It dissolves both sulphur and 
chlorine so that it is not easy to obtain it in a pure 
state. If unmixed india rubber is exposed to its 
action it will quickly become vulcanized. At ordi- 
nary temperatures the mixing action takes place, 



AND THE MANIPULATION OF RUBBER. 101 

though it is much accelerated by a slight applica- 
tion of heat. 

It is quite possible that this action may be of use 
to the reader in his manipulation of india rubber. 
Thin sheet may be vulcanized by being immersed in 
a solution of this substance in bisulphide of carbon 
followed by slight heating. The thin layer of 
caoutchouc left by evaporation of the chloroform 
solution of india rubber may thus be vulcanized so as 
to become comparatively strong and elastic. Where 
the same solution has been used as a cement or for 
patching overshoes and finishing the patch, a vul- 
canization can thus be given to it. 

The process is known as Parkes' cold curing pro- 
cess. 

A solution of one part of chloride of sulphur in 
forty parts of bisulphide of carbon is of good 
strength for rapid work. A thin article needs but an 
instant of immersion. It then is placed in a box or 
tray upon some talc powder and is heated to about 
104° F., (40° C). One minute of curing will suf- 
fice. It is advisable to wash off the articles after- 
wards in water or in weak lye to remove any traces 
of acid. 

Petroleum naptha can be used as the solvent in- 
stead of bisulphide of carbon. The latter substance 
has an exceedingly disagreeable odor, and its vapors 
must be considered rather injurious especially to 
those who are not accustomed to them. 

When thick articles are to be cured by this pro- 



102 RUBBER HAND STAMP MAKING. 

cess a much more diluted solution is used. One 
per cent, or less of the chloride of sulphur is the 
proportion used. The object of this is to enable 
a longer immersion to be employed so that the in- 
terior will be affected before the outer layers become 
too much charged with the vulcanizing material. 

In this short description of the Parkes curing 
process hints for a useful method may be found. 
The process is beyond doubt by far the simplest 
known for treatment of india rubber. Exactly 
what reaction takes place is unknown. Whether 
the sulphur or the chlorine is the acting vulcanizer 
has not as yet been determined. 

Its defect .is that it produces surface action, anal- 
ogous to casehardening. One method of avoiding 
this is to remove the articles from the sulphur 
chloride bath and at once to immerse them in water. 
This prevents the rapid volatilization of the solvent 
and an equalizing of the absorption ensues. 



CHAPTER XII. 

THE SOLUTION OF INDIA RUBBER. 

India rubber presents some difficulties in its 
solution. If a piece of pure gum just as received by 
the factory is placed in hot water it will swell and 
whiten after a while, but will not dissolve. If a 
similar piece is placed in benzole a similar but 
greatly exaggerated action takes place. The piece 
if left to soak for a day or more swells enormously, 
but very little solution is effected. 

The swollen india rubber can be removed from 
the benzole in a single piece. It will display all the 
layers and marks of the original piece which was 
perhaps of not one hundredth part of its volume. 
Some parts will be a perfect transparent jelly. 

It has been found that masticated india rubber 
dissolves with comparatively little difficulty. If 
the experimenter will place in a porcelain mortar, 
the jelly-like mass obtained as above detailed, and 
will rub it up thoroughly, it will be effectually mas- 
ticated. This requires a little patience, as the 
slippery material seems to elude the pestle. Yet 
eventually it will all be reduced to a perfectly homo- 
geneous mass. Its action while being rubbed up is 



104 RUBBER HAND STAMP MAKING 

very peculiar. At first no progress seems to be 
made. After a little the lumps yield to the friction. 
The rubber then begins to attach itself to the pestle 
and mortar, and begins to be drawn out into ever 
changing webs and threads. As the operation ap- 
proaches completion the material makes a snapping, 
crackling noise familiar to all rubber workers. 
When complete there will be no lump left, and the 
whole will be a uniform pulp. 

If beuzole or a volatile solvent has been used, the 
rubber will easily be removed from the mortar with 
a spatula or palette knife. If turpentine was the 
solvent it will be impossible to remove the last 
traces except after long standing or by solution. 

If replaced in the original solvent it will now come 
into nearly or quite perfect solution. This is the 
best way of masticating on the small scale. It is 
almost impossible to masticate untreated gum in an 
ordinary mortar. 

The dealers sell a special india rubber for the 
manufacture of cement and solutions. This is so 
treated by mastication that it dissolves with great 
readiness. It is also said that heating under pres- 
sure is used to dissolve it in some factories. 

Many solvents have been used and none work 
without some difficulty. Benzole, coal tar naptha, 
petroleum naptha, carbon disulphide, ether and 
chloroform, oil of turpentine and caoutchoucin are 
the best known. The naptha best suited for its 
solution is termed solvent naptha. It has a specific 



AND THE MANIPULATION OF RUBBER. 105 

gravity of .850 at 60° F. (15^° C); it boils at from 
240° F. (115#° C.) to 250° F. (121° C.) and on evap- 
oration should leave no more than ten per cent, of 
residue at 320° F. (160° C.) 

Payen recommends a mixture of 95 parts bisulph- 
ide of carbon with 5 parts of absolute alcohol. 

Commercial chloroform is apt to be too impure to 
act as a good solvent. It is apt to contain alcohol 
mixed with it as a preservative, which impairs its 
effectiveness. 

Some of these solutions are better suited than 
others for the deposition of thin layers by evapora- 
tion. Turpentine gives a very sticky and unman- 
ageable solution, which dries very slowly. Payen's 
solution and the chloroform and the benzole solu- 
tions may be cited as especially adapted for this 
purpose. Careful vulcanization by the cold curing 
method can be applied to articles made by such 
deposition from evaporation. 

In the case of all of them some form of mastication 
for the india rubber is needed. The simple mortar 
grinding of the gum swelled by the solvent is the 
only practical treatment without special apparatus. 

When it is remembered that fixed oils are de- 
stroyers of vulcanized or unvulcanized india rubber 
it will be obvious how important it is to use pure 
solvents. Too great care cannot be taken to pre- 
serve the liquids pure and free from such matter. 

A solid hydrocarbon may be used. Thus paraffin 
wax, such as candles are made of, when melted acts 



106 RUBBER HAND STAMP MAKING 

as a solvent. The resulting liquid solidifies when it 
cools, retaining an almost greasy feel. 

Boiling oil of turpentine is recommended by 
some for the solution of vulcanized india rubber. 
Phenyle sulphide, it is stated, will soften it so as to 
render it workable. The latter discovery is credited 
to Dr. Stenhouse. 

It is stated that a solution or pasty mixture of 
one part of caoutchouc in eleven parts of turpentine 
with one half part of a hot concentrated solution of 
sulphur (potassium sulphide) gives on evaporation a 
film neither tacky nor soft, a species of vulcaniza- 
tion taking place. 

It is of much interest to note that an aqueous 
solution of india rubber has been proposed in which 
the vehicle is a solution of borax in water. This is 
well known to be a solvent for shellac and other 
resins. It has been recommended often as a vehicle 
for rubbing up india ink. The ink made by mixing 
lampblack with the shellac solution is nearly water- 
proof. A shellac varnish is given by the plain solu- 
tion. 

The experiments upon india rubber were pub- 
lished in a recent trade paper. One method of 
making the solution is as follows. 

A solution of borax two fifths saturated is made 
by adding to two volumes of saturated solution 
three volumes of water. To this is added a solution 
of india rubber in benzole or other hydrocarbon of 
such strength and in such quantity as to contain 



AND THE MANIPULATION OF BUBBER. 107 

from three and one-half to four and one-half per 
cent, of india rubber referred to the borax solution. 
It is now vigorously shaken and heated to 120°-140° 
F. (49°-60° C.) and the agitation, not too violent, is 
continued until it cools. Ceara or Madagascar rub- 
ber answers best; Para is not so good for this for- 
mula. This may be termed the indirect or emul- 
sion method. 

For direct solution from two to three volumes of 
water may be added to three volumes of saturated 
borax solution. The india rubber is added in ex- 
tremely thin shavings and the solution is heated. 
For weak solutions the boiling point need not be 
reached. For strong solutions the heating should 
be done under pressure so as to bring up the pres- 
sure to one to three atmospheres. 

Such solutions may contain as much as eight per 
cent, of the gum. The mixture is liable to coagu- 
late or gelatinize just at the wrong time, but it may 
be of value as a vehicle or as a waterproofing agent. 
It deserves further investigation, which it is to be 
hoped it will duly receive. 

Great care is necessary in working with naptha, 
benzole, carbon disulphide and similar liquids. 
Their vapor is given off at ordinary temperatures 
and may travel some distance to a lamp or fire and 
become ignited and carry the flame back to the ves- 
sel. Their vapors are also anaesthetic and should be 
avoided as regards inhalation. 



CHAPTER XIII. 

EBONITE, VULCANITE AND GUTTA-PERCHA. 

Ebonite and Vulcanite. — These two well known 
substances are india rubber, in which the vulcaniza- 
tion process has been intensified. From twenty- 
five to fifty per cent, of sulphur is added in the 
mixing, and the curing is prolonged to several 
hours. A temperature of 275° F. (135° C.) for six 
to ten hours is sometimes recommended, but gener- 
ally a shorter period at the regular temperature, 
284° F. (140° C), may be employed. 

The mixed sheet is made and sold extensively for 
dentists' use. It is soft and flexible and very easily 
moulded. It is treated like the regular mixed sheet 
in every respect, except that plumbago brushed on 
the slightly oiled surface of the mould is recom- 
mended instead of the light colored talc, to prevent 
adherence. Wax where available is better than 
oil. 

Sometimes specimens are built up in sections. 
About an hour before full vulcanization in the 
fourth stage, new material can be added and will 
attach itself to the old. The stages of vulcaniza- 
tion are thus given by Bolas. 



AND THE MANIPULATION OF RUBBER. 109 

" Several distinct stages or steps may be traced 
during the curing of ebonite; and I wish to call 
your attention to some specimens illustrating these 
various stages. 

"Here, in the first place, is the plain mixture of 
sulphur and rubber, this being nearly white, and 
capable of becoming quite plastic or soft by the ap- 
plication of a gentle heat. 

" The second specimen illustrates the action of a 
very moderate degree of heat on the mixed material, 
this particular sample having been heated to 128° 
Centigrade for twenty minutes. It is, as you see, 
somewhat darkened, and has lost a little of its orig- 
inal softness; while a degree of heat which would 
have rendered the original mixture plastic, like 
putty, fails to make much impression upon it. 

"The third specimen illustrates the effect of a 
more prolonged heating, this sample having been 
heated for an hour to 135° Centigrade. It is olive 
green in color, and has acquired a certain amount 
of elasticity, resembling that of a rather inferior 
quality of vulcanized caoutchouc. 

" The fourth stage of curing is illustrated by this 
specimen, which you see is brown, and tolerably 
hard. Ebonite in this state refuses altogether to 
become plastic by heat, and a temperature of 150° 
maintained for half an hour or less would suffice to 
bring it to the fifth stage, or that of finished 
ebonite. 

"The fifth stage, or that of properly cured 



110 RUBBER HAND STAMP MAKING 

ebonite, is the goal to be arrived at in manufactur- 
ing the material. There should be no places where 
the curing is imperfect, a kind of defect which is 
likely to happen when articles of unusual thickness 
are vulcanized, and no portion of the ebonite should 
be spongy or honeycombed by air bubbles. 

" The sixth, or spongy state, is generally the 
result of over-heating, bubbles of gas forming in 
the material, and converting it into a kind of 
porous, cinder-like mass. 

"A specimen will now be handed round, which 
illustrates the third, fourth, fifth and sixth stages, 
as already described. The specimen in question 
was cured on a hot plate, this having probably been 
heated to 160° or 170° Centigrade; and you will be 
able to trace all gradations in the curing operation, 
from the first setting of the plastic material to the 
destruction of the ebonite by overheating." 

Cement for uniting pieces of the partially cured 
material may be made by rubbing up some of the 
untreated scrap with benzole. 

At the heat of boiling water, ebonite can be bent 
to a certain extent, which bend it retains on cooling. 
When warm an impression of a coin or relief die 
may be made on it by heavy pressure which it will 
retain. On heating the image disappears. If before 
heating the surface is planed off and the piece is 
heated the image formerly in intaglio will expand 
into relief. 

By the exact process of rubber stamp making 



AND THE MANIPULATION OF RUBBER. Ill 

excellent stereotype plates may be made of eb- 
onite. 

It can be turned at high speed in a lathe and pol- 
ished with fine 000 emery paper followed by a cloth 
bob with rotten stone, etc., and water or oil. Blot- 
ting paper, charged with the above or with tripoli, 
is excellent for polishing small surfaces by hand. 

Ebonite is a good connecting material between 
softer rubber and iron, the whole being vulcanized 
together ; the iron should be well roughened or 
cut into rasp-like or file-like projections. 

Ebonite is properly the name for black hard rub- 
ber, and vulcanite for the colored products such as 
used by dentists and others. ■ 

GUTTA-PERCHA. 

Gutta-percha is prepared by coagulation from the 
juice or sap of several trees, among others the 
Isonandra gutta, of Borneo and the East Indian 
Archipelago. The product gutta-percha is iden- 
tical in composition with india rubber. It is hard 
at all ordinary temperatures. 

Its manufacture includes purification and masti- 
cation. It is far more amenable to treatment than 
is india rubber. Many materials are mixed with it 
as adulterants or otherwise in the factories. 

It is more useful in the form of sheets. These 
when heated to 122° F. (50° C.) become pliable and 
can be moulded by pressure to any degree. At the 



112 RUBBER HAND STAMP M AKIN G 

temperature of boiling water it becomes pasty and 
adhesive, and at 266° F. (130° C.) it is so soft that it 
may be considered as melted. 

It is an admirable moulding material. Stereo- 
types and other relief or intaglio images can be 
made by pressing it while heated. These are often 
absolutely perfect reproductions of the original. 

Dishes for photographic purposes, etc., are easily 
made out of the sheet. By gentle warming they 
become pliable, and a greater heat makes surfaces 
capable of adhering by pressure. 

Tubes can be made by the squirting process, as 
used for india rubber. Wires are coated with it in 
a similar manner. 

It has several defects. It is not durable if ex- 
posed to the air with consequent changes of temper- 
ature. It is also too easily softened by heat, as of 
course no hot liquid can be introduced into a gutta- 
percha vessel. The Parkes cold curing process can 
be applied to it, which makes it more indifferent to 
heat. This is applied by dipping an instant and 
drying. After several repetitions the period of dip- 
ping is prolonged and ultimately it is left immersed 
some time. If left immersed at first it would dis- 
solve. 

It is soluble in most caoutchouc solvents, particu- 
larly in carbon clisulphide. 



CHAPTER XIV. 

GLUE OR COMPOSITION STAMPS. 

Stamps made from a mixture of glue, glycerine, 
and molasses or from similar mixtures are an excel- 
lent substitute for iudia rubber stamps. Properly 
made they possess all the flexibility that character- 
izes the rubber ones, while for fatty inks such as that 
used by printers and lithographers, which inks tend 
to destroy rubber stamps, they are much better. 
They are adopted by the United States government 
for making dating stamps for use in the Post Office 
Department ; by publishers of directories for print- 
ing advertisements on the edges of their publica- 
tions, and in many other cases. Our description 
shall follow as closely as possible the process and 
methods used in the United States- Post Office. 
They are there termed "composition blotters." 

The composition of which they are made is print- 
er's roller material. Nine and one-half pounds of 
fine quality glue are soaked in just enough soft 
water to cover it until it is thoroughly softened. 
It is then melted. In the Government Department 
a steam kettle is provided for the purpose. An 
ordinary glue pot will answer for smaller quantities. 



114 



RUBBER HAND STAMP MAKING 



When melted four and one-half pounds of best molas- 
ses and seven pounds of glycerine are added, and the 
whole is thoroughly mixed. The formula varies a 
little according to the prevailing temperature, less 
molasses being added when the weather is warm, and 
vice versa. Experience is here the best teacher. 
When well mixed it is poured out into tin pails 
whose inner walls or sides and bottom have been 




Model for Composition Stamp Mould. 



rubbed over with oil. It solidifies in cooling and 
becomes a clear brown jelly quite free from any 
stickiness or superficial moistness. 

In use it is turned out of the pails to which, 
owing to the oiling, it does not adhere. It is cut 
off as wanted, melted by heat and cast in oiled 
moulds. 

The latter are made of type metal to which one- 
third its weight of lead has been added. As model 



AND THE MANIPULATION OF RUBBER. 115 

for the mould or matrix a brass model of the 
stamp is employed. This represents a sort of oval 
based cut-off or truncated cone, about an inch 
high and a little over an inch long on its base. A 
flange extends outward from its base and a tube is 
provided to fit this flange. Its smaller end corre- 
sponds to the face of the stamp, and on it are en- 
graved in full relief any permanent characters, 




Composition Stamp Mould. 

circles or border lines, etc. Through its centre one 
or more apertures are made. Into these, changeable 
steel, iron or brass type may be introduced and set 
fast with plaster of paris. 

To make the mould, the brass model with its mov- 
able type set as required is placed upon a flat table 
or plate, face upward, and surrounded by the tube, 
as shown in partial section in the cut, page 114. The 
tube is a strip of sheet iron, which is bent around the 
flange and is secured in place by a wire twisted 
around it. The melted alloy (type, metal and lead) is 



116 RUBBER HAND STAMP MAKING 

poured into the space thus formed until it rises a 
quarter of an inch above the face of the model. In 
a few minutes it sets and is removed and allowed 
to cool. This gives a cup with the inscription and 
design depressed or in intaglio upon its inside base. 
This is shown in the cut, page 115, partly in section; 
it will of course be understood that the mould forms 
a complete cup. 

To make the stamp the interior surface of the 
mould is oiled with a stiff brush. It is not material 
what oil is used. The composition melted by heat is 
then poured into the cup, and is allowed to solidify. 
Owing to the conical shape of the mould it is 
readily removed. The mould must be hot but not 
too much so. 

In the Post Office stamps the date requires to be 
changed frequently. Some of the figures do duty 
for two or three days each month. Thus the figure 
8 is in the designation of three days, the eighth, 
eighteenth, and twenty-eighth. There are three 
changes involved therefore in connection with this 
day numeral. When a stamp mould or matrix is cast 
the place of numerals that are to be changed is 
filled with a blank space in the part where the type 
would otherwise come. A number is stamped in 
this space when needed, by means of an ordinary 
steel number-punch. 

When the number is to be changed the old char- 
acter is scraped or cut out, leaving a small irregular 
hollow. A very small piece of soft lead, about one- 



AND THE MANIPULATION OF RUBBER. 117 

sixteenth of an inch on each side, is dropped into 
the hollow. AVith a fiat faced punch it is flattened 
out, and on it the new number is impressed by a 
steel punch. This operation is repeated a great 
many times before the matrix is worn out. 





OPEN. 



Composition Stamp Handle. 



In the cut, page 115, one number is shown as 
stamped into the soft lead, and at the other end of 
the stamp is a blank space ready for a number. 

The casting of a stamp is so extremely simple 
that no attempt is made to use movable type, as in 
permanent rubber dating stamps. 

While it is obvious that these composition stamps 
could be attached directly to wooden handles, a spe- 



118 BUB BEE HAND STAMP MAKING 

cial style of handle, shown in the cuts, is employed 
by the Post Office. A wooden handle carries at its 
end a brass base, to which is pivotted a swinging 
piece that is perforated by a conical oval aperture a 
little larger than the small end of the stamp. The 
edges of this aperture are slightly rounded. 

It is swung around as shown in the first figure, 
and the stamp, previously moistened on its sides, is 
forced in. If the stamp is properly made it is sur- 
prising how much force may be used to insert it. If 
the edges of the brass swinging piece ape not rounded 
there is danger of the composition being cut. The 
stamp in its brass frame is then swung back over 
the brass base, where it is secured by a catch. The 
stamp is now ready for use, as shown in the second 
figure of the cut. 

It is imperative that no aqueous or glycerine ink 
be employed for continuous work with such stamps. 
Common printers' ink is perfectly satisfactory, and 
the work may be nearly or quite as good as that ex- 
ecuted by an india rubber stamp. 

The Post Office manufactures a pad for use with 
printers' ink into whose manufacture the same com- 
position enters. The ink retainer is a piece of fine 
felt, one-quarter to one-half an inch thick. This is 
placed in the bottom of a shallow steel mould, where 
it enters for half its depth into a recess that it ac- 
curately fits. The composition from old stamps, 
melted up, is then poured upon and around it, the 
mould being previously oiled. When it is full a 



AND THE MANIPULATION OF RUBBER. 119 

piece of strong manilla paper, of the area of the felt 
only, is placed upon the bottom of the glue pad on 
its centre, which as it lies in the mould is its upper- 
most part. The paper adheres strongly as the glue 
hardens. Eventually it is turned out of the mould, 
and a pad, shown in the cut, is produced. The 
dotted lines show the limits of the felt pad. The 
glue composition underlies, surrounds and extends 
outwards from the felt portion. It is found that 
the elasticity of the composition makes the pad 




Composition Ink Pad. 



much pleasanter for rapid stamping. 

The above description gives the clew to making 
any stamp of this description. The matrix may be 
of dental plaster, or of oxychloride of zinc cement. 
The mould may be built up of type of any kind. 

The composition is so cheap that the stamp can 
be made quite thick. This gives it a high degree 
of elasticity and adaptability to uneven surfaces. 
It may be mounted by adherence upon a flat board 
or block, provided, if necessary, with handles. If the 



120 RUBBEB HAND STAMP MAKING. 

board or block is placed upon the composition while 
it is still warm and liquid, as it solidifies the board 
and composition will adhere with great tenacity. 

All moulds or surfaces to which it is desired that 
the melted composition shall not adhere must be 
oiled. 

The moulds must not be cold or the comjDosition 
will not enter the fine divisions. If on the other 
hand they are too hot the mixture will adhere. 
Experience will teach the right conditions for suc- 
cess. 

Below are given other formulae for roller composi- 
tion. The formula already given in this chapter is 
that used by the United States Post Office Depart- 
ment. 

I. " Old Home Receipt:" Glue 2 lbs., soaked over 
night, to New Orleans molasses 1 gallon. Not 
durable, but excellent while it lasts. 

II. Glue 10^ lbs., molasses %y 2 gal., Venice tur- 
pentine 2 oz., glycerine 12 oz.; mix as directed 
above. 



CHAPTER XV. 

RUBBER IN SURGERY AND DENTISTRY. 

While the preceding chapters of the present 
work are devoted almost exclusively to a descrip- 
tion of the method of making rubber stamps and 
type, yet this is but one of the multitudinous uses 
to which rubber is adapted under modern manu- 
facturing conditions. In almost every art and 
trade rubber plays an important part and each 
year and month the demand for this valuable 
natural product increases. The amount of rubber 
annually consumed is almost unbelievable and yet 
a large portion of the rubber used up or worn 
out is actually reclaimed. Quite recently an 
examination of the dust from streets and parks 
of cities, disclosed the fact that about 12 per cent 
of the dust was composed of rubber worn from 
the rubber tires of vehicles, — an amount well 
worth reclaiming and which would amply repay 
the trouble and cost of street cleaning. 

Perhaps the most valuable and important use 
to which rubber is put, is the manufacture of 






122 RUBBER HAND STAMP MAKING 

surgical and dental goods. Modern surgery would 
be practically impossible without rubber and the 
dentist could hardly succeed at all without the 
aid of this wonderful gum. 

Rubber or gutta percha was apparently first 
used by the medical world in 1822 when a Mr. 
Montgomerie of Singapore found the natives using 
it for whips, and at once grasped its possibilities 
for use in making braces and similar surgical 
appliances, and in 1842 he recommended the use 
of rubber for splints, etc., to the medical board 
of Calcutta. In 1844, the Society of Arts of Lon- 
don awarded Mr. Montgomerie a gold medal in 
recognition of his useful discovery and the bene- 
ficial results from its use in surgery. After this 
time the use of rubber and gutta percha for surgi- 
cal appliances and instruments rapidly increased 
and soon became universal. 

India rubber has perhaps rendered its greatest 
service to modern medical practice in the form 
of drainage tubes. Upon the proper drainage of 
wounds depends to a great extent their healing. 
While many other substances have been used as 
drainage tubes, yet more drainage tubes of rubber 
are used than of all other substances combined. 
In the first place its elasticity renders it applica- 
ble to almost any shaped wound; it is not readily 
broken; it resists most chemicals; it is cheap 



AND THE MANIPULATION OF RUBBER. 123 

and is easily sterilized. As tourniquets, rubber 
bandages, ice-caps, water bottles, syringes, sheet- 
ing, aprons, gloves, instruments, handles, cathe- 
ters, bougies, and in various other ways India 
rubber or gutta percha is widely and universally 
used in medicine and surgery. 

A very valuable use to which rubber is also put 
in surgery is in the manufacture of artificial 
limbs. Many artificial limbs are composed entirely 
of rubber, while practically all modern artificial 
limbs have rubber in some form employed in 
their manufacture. Some of the best limbs made 
in America are wholly composed of rubber, with 
a small core of wood, while others use rubber only 
as buffers at the joints to take up or absorb the 
jar or concussion in the use of the artificial hands 
or feet. So excellently made and so well adapted 
to the purpose are rubber hands, that many 
wearers of these artificial members can use them 
to handle small articles and can write almost as 
well as with the hands provided by nature. Arti- 
ficial rubber feet defy detection and can be used 
in riding bicycles, walking, running, dancing and 
other ways with practically the same security and 
ease as real feet. 

The introduction of vulcanized rubber into 
dentistry marked the greatest epoch in its advance- 
ment and opened a new field for dental surgery. 



124 RUBBER HAND STAMP MAKING 

While artificial teeth of ivory, bone, wood and 
metal were actually known and used by the old 
Egyptians yet the art of dental surgery practically 
died out until the middle of the 17th century. 
Even then dentistry was crude and primitive and 
it was not until the advent of rubber and the 
discovery of vulcanization that dentistry, as now 
known, came into existence. 

Hard rubber as a material for plates for holding 
artificial teeth has no superior, and even gold, 
which is far more costly, is no more durable and 
far less comfortable. Rubber is exceedingly dura- 
ble and will last for years without suffering injury 
or change from the secretions of the mouth or 
foods, and possesses the great advantage of being 
readily colored to match the real gums while 
undergoing vulcanization. Another most important 
point in favor of rubber plates for teeth is its 
cheapness; thousands of people who could not 
afford gold plates are rendered happy and able 
to eat their daily bread in comfort by the use 
of hard rubber plates for their teeth. Aside from 
its use in making artificial teeth, rubber is also 
used by dentists for dams and sheeting while 
gutta percha is often used in filling teeth. 

It is estimated that over thirty-five tons of 
rubber are annually used in the manufacture of 
artificial teeth alone, and soft rubber has a still 



AND THE MANIPULATION OF RUBBER. 125 

wider field in surgery and medicine, so that the 
total consumption of the gum in these lines of 
work is enormous. 

Practically all rubber articles used in surgery 
and dentistry are moulded or pressed into shape 
while the unvulcanized rubber is hot, and are 
then vulcanized, — much in the same manner as 
in the manufacture of rubber stamps already 
described. Plates for teeth are made in plaster 
moulds, which are in turn made from impressions 
of the roof of the mouth made by pressing a 
special form of moulding wax against the flesh. 
The wax used is readily softened in warm or 
hot water, and while still warm and plastic, is 
pressed firmly against the roof of the mouth and 
from the impression thus obtained a plaster matrix 
is cast in fine dental plaster. The position of the 
teeth on the other jaw is obtained by biting 
firmly into another strip of wax held in a specially 
designed metal holder. The plaster moulds being 
ready, the false teeth of porcelain are set in posi- 
tion, the raw rubber pressed in the mould, the 
whole clamped firmly together and placed in the 
vulcanizer until thoroughly ''cured. " 

The process is very simple and requires no 
more skill or technical knowledge than in making 
stamps or similar objects, but to facilitate mat- 
ters, and render the operations more successful 



126 RUBBER HAND STAMP MAKING 

and certain, forms, moulds, teeth and rubber come 
prepared in various forms, colors and sizes to 
suit all variations in the patients' mouths or 
teeth. 



CHAPTER XVI. 

Rubber Tires. 

constructing and repairing rubber vehicle 
tires, rubber preparations, chemical 
or cold vulcanizing. 

Wide and important as are the uses of rubber 
in surgery and dentistry, yet of almost equal 
importance and of far greater volume and cash 
value is its use in the manufacture of rubber 
tires for modern vehicles. Automobiles, bicycles, 
motorcycles, etc., were made practical and pos- 
sible through the use of rubber as tires for the 
wheels and the comfort, speed and life of all motor 
vehicles depend largely upon the quality of the 
rubber used for tires and the care taken in its 
manufacture. 

Rubber tires may be broadly divided into two 
distinct classes; solid tires and pneumatic tires. 
In the former, the tire consists of a solid, or hollow, 
band or rim of rubber strengthened by strips of 
metal, fiber or wires placed within its mass and 
the whole cemented or vulcanized on the wheel 
(Fig. 1). Such tires answer very well for small 



128 RUBBER HAND STAMP MAKING 

vehicles, as baby carriages, velocipedes and invalid 
chairs, and are also largely used on commercial 
vehicles, trucks, etc., as well as on many horse- 

$ot/d T/res 




3t* 9 U Tu J>e Dou b/e Tub c( Am /nner tllbe} , 

Fig. 1. — Sections of Rubber Tires of Various Types. 

drawn carriages, hacks, cabs and light wagons. 
The solid tires wear away rather rapidly, are heavy 
and cost a great deal if made of solid rubber of 
good quality, and do not possess the resiliency 
and cushion effect of the pneumatic tires. These 
consist of a hollow casing, or shoe, of rubber and 
fabric which is inflated by air and may be readily 
attached to or detached from the wheel itself. 
In the early days of rubber tires the pneumatic 
tires were made in the form known as "single 



AND THE MANIPULATION OF RUBBER. 129 

tube" and were merely an endless tube of rubber 
and fabric inflated with air. Such tires soon 
became leaky and were then useless, and conse- 
quently proved very expensive and unsatisfactory. 
The system of "double tube" or "inner tube" 
construction was then invented, and to-day prac- 
tically all the pneumatic tires in use are of this 
character of construction. 

The inner tube, or double tube tire, consists 
of a heavy casing of rubber and fabric made in 
semicircular or circular section, with the inner 
side open. Within the cavity of this casing . a 
thin rubber tube is placed, and when the whole 
is attached to the wheel of the vehicle the inner 
tube is inflated. By this method much longer 
life is insured than by the single tube system, 
for in case of wear or injury to either inner tube 
or the outer casing the tire may be removed and 
a new tube or a new casing substituted as required. 
Pneumatic tires were first made in Europe, and 
were first introduced into the United States by 
Mr. E. J. Willis of New York in 1889. Since 
that date the use of the pneumatic tire has spread, 
and hundreds of factories are now manufacturing 
these goods throughout the country, while the 
number annually used runs into millions, — in 
fact a single factory sold over one million tires 
during the year of 1911. As the rubber used in 



130 



RUBBER HAND STAMP MAKING 



these tires must be of the best grade, and free 
from reclaimed or "shoddy" stock, each tire made 
must be built from new rubber and it can there- 
fore be readily seen what an enormous amount 
of rubber is annually consumed in this branch 
of the rubber industry alone. In the details of 
construction, each maker of tires has his own 
ideas and system, but in all the process is more 




jTjg. 2. — Construction of Pneumatic Tire. 

or less similar. In Fig. 2 is illustrated a section 
and diagram of a well-made tire, showing how 



AND THE MANIPULATION OF RUBBER. 131 

it is built up of alternating layers of rubber and 
fabric. The inner layer A is ITJ^-ounce Sea 
Island cotton duck or fabric, cut on the bias and 
placed over a form or mould. This fabric is tho- 
roughly impregnated with pure rubber and over 
it is moulded a layer of pure Para rubber, B; 
C is another layer of cotton duck, with the lap 
or seam started exactly opposite from the layer A ; 
D is another layer of rubber, the same as B, and 
E another layer of duck, while F, G, H, and / 
are likewise alternating layers of duck and rubber. 
Each layer of duck has a tensile strength of 450 
pounds or more, and each joint in the fabric is 
opposite that of the layer beneath with a long 
overlap. Over the last layer of duck a heavy strip 
of soft, pure rubber is placed, J, and is known 
as the ''cushion and breaker strip." This serves 
as a soft cushion to absorb the jar and blows 
to which the tire is subjected, and also prevents 
the various layers of cotton and rubber from 
loosening. Within the soft rubber cushion a strip 
of loosely-woven cotton fabric of extra strength 
is placed, and this "breaker strip" serves to bind 
the cushion rubber together and prevent its tear- 
ing or separating while in use. Over the whole 
of the various layers and cushion the binder 
strip, K, is then placed. This is a layer of specially 
prepared rubber which forms the outer wall of 



132 RUBBER HAND STAMP MAKING 

the tire on the sides, and which binds all the 
other parts of the tire together. Over the central 
part of the binder a heavy "tread" of selected 
tough rubber is placed, M, and upon the tough- 
ness, composition and quality of this tread depend 
in great measure the life and durability of the 
whole tire. When the tire is completely moulded, 
or built up, it is thoroughly vulcanized, and in 
this operation the rubber-impregnated cotton, the 
rubber between the fabric and the cushion, binder 
and tread are all thoroughly and firmly united and 
formed into a solid, uniform mass. 

Good tires require a great deal of time and 
labor to construct, to say nothing of the cost of 
material, and the high prices asked for such 
tires is therefore not surprising or unreasonable. 
Of course, many cheap, poorly-constructed tires 
are made, but such goods wear badly, and when 
once injured, broken or worn are useless; whereas, 
a really good tire may be repaired and used over 
and over until completely worn out. Most reliable 
makers guarantee their tires for 5,000 miles and 
many tires are frequently used for from 12,000 
to 20,000 miles. 

The commonest accidents to tires are "blow- 
outs" and "punctures." Blow-outs are caused 
by faulty construction, poor inflation, rotting of 
fabric, overloading or excessive speed, and consist 



AND THE MANIPULATION OF RUBBER. 133 

of a hole or tear blown clear through the casing 
from the inner side. Blow-outs, if not too large, 
may be repaired by relining and vulcanizing. 
Punctures are small holes made by running over 
nails, sharp stones, glass, etc., and are readily 
repaired. The greatest enemy to tires is heat, 
and this is usually caused by excessive speed, 
owing to the constant friction of the various 
fibers and threads of the cotton fabric rubbing 
against one another. More or less heat is also 
generated by the friction of the tire upon the 
road itself, but this is seldom sufficient to cause 
damage. 

The harder a tire is inflated the less chance 
there is of friction occurring in the tire itself, 
and for this reason every tire should be kept 
properly inflated, according to the directions 
furnished by the maker. 

The business of repairing tires has now grown 
to enormous proportions, and large factories are 
engaged solely in making appliances and materials 
for this industry. The usual method of repairing 
a broken or punctured tube is to place a raw 
rubber patch over the hole, cement it in place and 
vulcanize both patch and cement. In the case 
of outer casings the work is far more difficult 
and complex, for the casing may require either 
a new tread or a new lining, according to the 



134 RUBBER HAND STAMP MAKING 

damage to be repaired. In the case of a new tread, 
the parts are thoroughly cleansed, soft rubber 
composition spread over the place to be repaired, 
the mass held in position by a winding of tape 
or cloth and the whole vulcanized. 

Where a new inner lining or fabric is required, 
the webbing, impregnated with rubber, is moulded 
in the inside of the casing and is then vulcanized. 
Vulcanizing for repair work is usually accomplished 
by steam heat, but numerous portable vulcanizing 
outfits for use with gasoline, alcohol, gas, kerosene 
or electricity are now made and for sale at most 
reasonable prices, and with one of these outfits 
any user of rubber tires can readily make his own 
repairs. 

Great advances have been made in the lines of 
rubber cements, rubber compounds and curing 
or vulcanizing methods, since the advent of the 
rubber-tired vehicle. Rubber cements are now 
on sale which are so easily used and of such excel- 
lent quality that vulcanization is entirely unneces- 
sary under ordinary conditions, and by patching 
the rubber article with a prepared patch and 
one of the various standard cements, the article 
repaired will be as good as new. 

Other patches and materials are made which 
are coated with strong adhesive rubber prepara- 
tions requiring no cement, while various com- 



AND THE MANIPULATION OF RUBBER. 135 

positions of rubber for filling holes, cuts, tears, 
etc., in rubber articles are widely used. Such a 
great number of these preparations are now on 
the market that it is hard to know what to use 
or what is good and what not, but practically 
any of the various preparations put up by reliable 
firms will prove satisfactory for the purpose for 
which they are designed. 

Among the various preparations the following 
have all been tested thoroughly by the writer 
and have been found to fulfill all the claims of 
the manufacturers and can be recommended most 
highly. Cements for patching: "Fisk," "Dia- 
mond," "Goodrich," "Stickfast," "Willis." Cements 
for patching (to be used with "acid cure"): "Good- 
rich," "Half and Half," "C.O.T.," "Congo," 
"M & M," "Pluto," "Hazenoid." Vulcanizing 
preparations (acid cures): "M & M," "Vulcanoid," 
"C.O.T." Cement for vulcanized work: "Good- 
rich," "Hazen-Brown," "M & M." Prepared 
patches for use without cement: "Wonder- 
worker," "Victor," "Continental." Filling com- 
position for cuts in casings: "Phil-Kut," "Gum- 
Gum," "Plastic," "M & M," "Kneadit," "Rubber- 
Tread," "Nu-Tread." Portable vulcanizing out- 
fits, steam: "Shaler," "National." Portable vul- 
canizing outfits, electric: "Shaler." Portable 
vulcanizing outfits, alcohol: "Shaler." Portable 



136 RUBBER HAND STAMP MAKING 

vulcanizing outfits, gasoline: "Shaler," "Stitch 
in Time," "Imperial," "Pig." By merely follow- 
ing the plain directions furnished with each of 
these various compositions or vulcanizing outfits, 
anyone can make satisfactory repairs in either 
casings or tubes, and aside from saving the cost 
of having it done outside, the satisfaction of 
knowing just how your repairs are made and 
how thoroughly the work is done, is of great 
importance. 

Many excellent tires are constantly ruined 
through neglect of small cuts, bruises, etc., and 
these should always be cleaned and filled with 
one of the various plastic fillers mentioned above. 
In using any preparation of rubber however the 
greatest care should be taken to do the work 
thoroughly and properly, for a small neglect in 
cleansing the material to be repaired or in other 
small matters will result in a poor and unreliable 
job which cannot be depended upon. 

Within the past few years great improvements 
have been made in methods of vulcanizing or 
"curing" rubber, especially when in the form 
of small patches or other repair work. Not only 
have the small compact and portable vulcanizers 
been highly perfected but various chemical methods 
of curing have been invented and brought into 
general use. These cold, or chemical, methods 



AND THE MANIPULATION OF RUBBER. 137 

are commonly known as "acid cures" and consist 
of certain chemicals containing some form of 
sulphur which applied to the raw rubber acts 
in the same manner as heating with sulphur. 
The preparations vary considerably in their com- 
position but usually consist principally of sulphur 
chloride, benzine, and carbon bisulphide. They 
are highly inflammable and explosive and great 
care should be taken not to use them near a 
flame or in the vicinity of a hot stove or similar 
object. 

The preparation is brushed over the raw rubber, 
and through the action of the sulphur contained 
in the solution the rubber is quite thoroughly 
vulcanized. For small work this method is far 
easier and cheaper than by the heating process 
and many rubber stamps and similar articles are 
now vulcanized by one of the various chemical 
methods. 

So enormous has the consumption of rubber 
become that the demand has far exceeded the 
supply and in the constant search for new rubber- 
producing plants, various trees, shrubs and vines 
have been found to furnish rubber or rubber-like 
gums or sap that are now used extensively as 
a substitute for rubber or as an adulterant of 
pure rubber. Among these may be mentioned 
the Balata rubber from a large forest hardwood 



138 RUBBER HAND STAMP MAKING 

tree of the West Indies and tropical America; 
Guayule rubber from a Mexican shrub; Sapota 
rubber from a tropical fruit tree, and Chicle rubber 
from another common fruit tree of tropical America. 
Balata rubber is very good and is widely used 
and for many purposes compares favorably with 
true Para rubber. Guayule is also extensively 
used and is produced in large quantities from a 
plant until quite recently considered worthless. 
The milky juice of the Sapota tree furnishes 
the Sapota rubber and Chicle of commerce and 
the latter is of great value for use in manufactur- 
ing various confections, such as chewing gums, etc. 
Rubber articles, when kept in a warm, dry 
place or in a very cold spot, often grow quite 
hard and inelastic; and while excessive hardening 
of rubber goods is usually a sign of inferior quality 
in the rubber, yet the highest grade goods are 
at times subject to this trouble. Most rubber 
articles may be readily softened by treatment 
with dilute ammonia, — about one part of ammonia 
to two parts of water. Before treating with this 
solution the articles should be thoroughly cleansed 
by scrubbing with a stiff brush and warm water. 
Place the cleansed articles in the ammonia and 
let them remain until the ammonia has evaporated, 
usually from one to two hours. After treatment 
with ammonia the goods should be rinsed with 



AND THE MANIPULATION OF RUBBER. 139 

a dilute solution of glycerine and water, thoroughly 
wiped and dried and stored in a cool spot away 
from the light. 

Another method for softening hard or brittle 
rubber goods is to place them in a hot aqueous 
solution of tannic acid and tartar emetic. Next 
transfer them to a cold solution of tannic acid 
and calcium sulphate. Mix the two solutions 
and heat to boiling point and place the rubber 
goods in this hot solution. The treatment should 
be continued for from one to four days, according 
to the size and nature of the articles. 

Old rubber stoppers that have become hard 
and useless may be revived by soaking in a 5 
per cent soda lye solution for about ten days 
at from 85 deg. Fahr. to 104 deg. Fahr., replacing 
the lye from time to time. The stoppers should 
then be thoroughly washed and the softened 
outer surface scraped off with a dull knife until 
the firm, elastic portion is reached. The stoppers 
should then be rinsed with warm water and will 
be found quite soft and flexible. They may be 
readily trimmed with a sharp knife wet with 
cold water and soft soap. 

For many purposes reclaimed rubber is widely 
used and answers as well as new, pure rubber. 
The scraps, old rubber, waste, etc., is first boiled 
in strong caustic soda or in sulphuric and hydro- 



140 RUBBER HAND STAMP MAKING 

chloric acid until all cloth, paint, fillers, etc., are 
dissolved and separated and the rubber is then 
ground and pulverized between rollers and pressed 
into sheets. 

Other processes include mixing the reclaimed 
rubber with mineral oil or benzol and steam under 
hydraulic pressure while an adulterated mixture 
or composition rubber is formed by adding the 
reclaimed rubber to hot linseed oil until dissolved, 
when coal tar or asphalt is added. When thorough- 
ly combined the mass is heated to a much greater 
temperature and air is forced through the mass. 
The resulting compound, when cool, is very tough 
and flexible and is of great value for insulating 
electric wires, cables, etc. 

For many years various attempts have been 
made to discover or invent a satisfactory artificial 
rubbers but although various compounds have 
been made which in a way answer as a substi- 
tute, yet none fulfills all the requirements. The 
so-called "Kerite" consists of a mixture of: 

Cottonseed oil 14 parts 

Linseed oil 14 

Asphalt 8 

Coal tar 8 

Sulphur 10 

Camphor V2 



AND THE MANIPULATION OF RUBBER. 141 

By combining a mixture of: 

Cottonseed oil 27 parts 

Coal tar 30 " 

Earthy matter 5 

with : 

Rubber 20 parts 

Litharge 5 

Sulphur 1 



n 



a tough, rubber-like mass is formed which is 
widely used in place of pure rubber for stoppers, 
bumpers, etc. 

Recently, also, various experiments have been 
made with compounds obtained from turpentine 
and coal tar, and excellent results obtained, but 
the process is long and complicated and the 
artificial rubber thus produced has proved more 
expensive than the genuine article. While these 
various substitutes have proved valuable for many 
purposes, yet no one has yet discovered anything 
that will take the place of Nature's product, and 
a vast fortune awaits the fortunate discoverer 
of a true artificial rubber that can be produced 
as cheaply or cheaper than the real article. 



CHAPTER XVII. 

THE HEKTOGRAPH. 

For obtaining multiple copies of writing, the 
apparatus called the Hektograph or Papyrograph 
has been extensively adopted. In general terms it 
consists of a tray filled with a jelly like composition. 
Any imprint made upon the surface with aniline 
ink can be transferred to paper by simple pressure. 
The tray filled with composition is called the tablet. 
It is thus prepared. 

The tray may be made of tin or even of paste- 
board or paper, and should be about one half an 
inch deep. It may be of any size, according to the 
work it is to do. The composition is made from 
the best gelatine and glycerine. One ounce by 
weight of gelatine is soaked over night in cold water, 
and in the morning the water is poured off, leaving 
the swelled gelatine. Six and one-half fluid ounces 
of glycerine are now heated to about 200 F. (93 C.) 
on a water bath preferably, and the gelatine is added 
thereto. The heating is continued for several hours. 
This operates to expel the water and to give a clear 
glycerine solution of gelatine. 

The composition is then poured into the tray, 



AND THE MANIPULATION OF RUBBER. 143 

which must be perfectly level in order to obtain a 
a surface nearly even with the edge. It is then 
covered so as to keep off the dust. The cover of 
course must not come in contact with the smooth 
surface. In six hours it will be ready for use. 

The original copy that is to be reproduced is 
made upon ordinary paper in aniline ink. One 
formula for the ink reads as follows: Aniline violet 
or blue (2KB or 3 B) 1 oz., hot water 7 fluid oz. ; 
dissolve. After cooling add alcohol 1 fluid oz. 
and glycerine % fluid oz., a few drops of ether and 
a drop of carbolic acid. Keep in a corked bottle. 
Other formulae are given in chapter XVII. 

The writing is executed with an ordinary steel 
pen. The lines should be rather heavy so as to show 
a greenish color by reflected light. 

The surface of the pad is slightly moistened with 
a wet sponge and is allowed to become nearly dry. 
The paper is then laid upon it and smoothed down. 
This is best done by placing a second sheet over it 
and rubbing this with the hand. No air bubbles 
must remain between the copy and the tablet, and 
the paper must not be shifted. 

It is allowed to remain for a minute or less 
and is then raised by one corner and stripped 
from the gelatine surface. It will have left the 
reversed copy of its inscription perfectly reproduced 
upon the tablet. 

At once a piece of ordinary writing paper of the 
desired size and quality is laid upon the tablet. 



144 



RUBBER HAND STAMP MAKING 



smoothed down, and stripped off, when it will be 
found to have taken witii it a complete copy of 
the inscription or writing. This is repeated over 




The Hektograph. 

and over again with another sheet of paper, until 
the ink on the pad is exhausted. Fifty or more 
good copies can be thus obtained. 

As soon as the work is completed the remains of 
the ink should be washed off with a moist sponge 



AND THE MANIPULATION OF RUBBER. 145 

and the tablet, after drying a little, will be ready for 
a second operation. 

Some practice is required to ascertain the proper 
strength of the writing and degree of wetness of the 
surface. When the gelatine surface becomes im- 
paired it can be remelted in a water bath if it is not 
too dark from absorption of ink. 

French M in istery of Public Work Formula. — Glue 
100 parts, glycerine 500 parts, finally powdered 
kaolin or barium sulphate 25 parts, water 375 parts. 
Use a little hydrochloric acid in the water for 
washing off the pad after use. 

Hektograph Sheets. — Four parts of glue are soaked 
in five parts of water and three parts of ammonia 
until soft. It is then heated and there is added to 
it three parts of sugar and eight parts of glycerine. 
The mixture is applied to blotting paper. This is 
saturated with it, and successive coats added until a 
smooth surface is produced on one side. This is 
the side for reproduction. It is used like the regular 
tablet except that it is claimed that sponging off 
the writing is not necessary. Owing to the capillary 
action developed by the blotting paper it is sup- 
posed to be self-cleaning by standing. 



CHAPTER XVIII. 

CEMENTS. 

Before cementing vulcanized rubber the surface 
should be roughened or still better it may be seared 
with a red hot iron. For bicycle tyres this is espe- 
cially to be recommended. 

Cement for Outs in Bicycle Tyres, Rubber Belts, 
etc. — Carbon bisulphide, 5 ounces; gutta-percha, 5 
ounces; caoutchouc, 10 ounces; fish glue, %y 2 
ounces. After it is applied and has dried the 
excess can be removed with a wet knife. Bad cuts 
should first be stitched up. 

Bicycle Tyre Cement to fasten Tyres to Rims. — 
Equal parts of pitch and gutta-percha are melted 
together. Sometimes two parts of pitch are pre- 
scribed. This cement has extended applica- 
tion. 

Cement for Paper Boats and for Mending Rubber 
Goods. — Fuse together equal parts of pitch and 
gutta-percha, and to this add about 2 parts of lin- 
seed oil containing 5 parts of litharge. Continue 
the heat until the ingredients are uniformly com- 
mingled. Apply warm. 

Waterproof Cement. — Shellac, 4 oz; borax, 1 oz; 



AND THE MANIPULATION OF RUBBER. 147 

boil in a little water until dissolved, and concentrate 
by heat to a paste. \ 

Another.— 10 parts of carbon disulphide and one 
part of oil of turpentine are mixed, and as much 
gutta-percha is added as will readily dissolve. 

Cement for Mending Hard Etcbber.—Fnse together 
equal parts of gutta-percha and genuine asphaltum; 
apply hot to the joint, closing the latter immedi- 
ately with pressure. 

Glue to Fasten Leather, etc., to Metals.— 1 part 
crushed nut galls digested 6 hours with 8 parts dis- 
tilled water and strained. Glue is macerated in its 
own weight of water for 24 hours, and then dis- 
solved. The warm infusion of nutgalls is spread 
on the leather; the glue solution upon the rough- 
ened surface of the warm metal; the moist leather 
is then pressed upon it and dried. 

Marine Glue, Various Formulce.—I. Dissolve 1 
part of india rubber in 12 parts of benzole, and to 
the solution add 20 parts of powdered shellac, heat- 
ing the mixture cautiously over a fire. There is 
great danger of conflagration. Apply with a brush. 

II. Caoutchouc, 1 oz; genuine asphaltum, 2 oz; 
benzole or naptha, q. s. The caoutchouc is first dis- 
solved (as described in chapter XII.), and the 
asphaltum is gradually added. The solution should 
have about the consistency of molasses. 

Cement for Vulcanized India Rubber. —Stockholm 
pitch, 3 parts; American resin, 3 parts; unmixed 
india rubber, 6 parts; oil of turpentine, 12 parts. 



148 RUBBER HAND STAMP MAKING 

Heat and mix very thoroughly. More oil of turpen- 
tine may be added as required. 

Gutta-Percha Cement for Leather. — Soak gutta- 
percha in boiling water. Soften in benzole after cut- 
ting up for a day. Heat on a water bath until the 
greater part of the benzole is expelled. When cool 
it will solidify. Use by heating. 

Cement for Rubber Shoes. — 

(1) Chloroform 280 parts. 

India rubber (masticated) 10 " 

(2) India rubber 10 " 

Resin 4 " 

Venice turpentine 2 " 

Oil of turpentine 40 " 

For first solution dissolve by mastication. For 
second, melt the finely divided gum with the resin, 
add the Venice turpentine and finally the oil of tur- 
pentine. Use heat if necessary. Mix both solu- 
tions finally. To apply, saturate a piece of linen 
with the cement and apply to the spot previously 
coated with the cement. As it dries apply a little 
more as required. A finishing varnish is given in 
the last chapter. Parkes* cold curing process may 
be applied as described in chapter XL 

Chatterto?i's Compound for uniting sheets of 
gutta-percha in cable cores and for general work 
with gutta-percha coated wires. — Stockholm tar, 
1 part; resin, 1 part; gutta-percha, 2 parts. 

Waterproofing for Wooden Battery Cells. — Resin, 
4 parts; gutta-percha, 1 part; boiled oil, a little. 



AND THE MANIPULATION OF RUBBER. 149 

Another Formula. — Burgundy pitch, 150 parts; 
old gutta-percha in fine shreds, 25 parts; ground 
pumice stone, 75 parts. Melt the gutta-percha and 
mix with the pumice stone and then add the pitch, 
melting all together. Apply melted and smooth off 
with a hot iron. 

Cement for Celluloid. — Shellac, 1 part is dissolved 
in spirits of camphor 1 part, with 3 to 4 parts strong 
alcohol. It is applied warm and the parts united 
must not be disturbed until the cement is hard. 



CHAPTER XIX. 

INKS. 
KUBBER STAMP INK. 

Aniline blue soluble, 1 B 3 parts. 

Distilled water 10 " 

Acetic acid 10 " 

Alcohol 10 " 

Glycerine 70 " 

For other colors the following aniline colors may 
be substituted in proportions given: 

Methyl violet, 3 B (violet) 3 parts. 

Diamond fuchsin I, (red J 2 " 

Methyl green yellowish 4 " 

Vesuvin, B (brown) 5 " 

Nigrosin, W (blue black) 4 " 

For very bright red 3 parts of Eosin BBN. are 
used. In this case the acetic acid must be omitted. 
In all cases the colors should first be rubbed up 
with the water in a mortar, and the glycerine 
should be added gradually. These inks will answer 
for the hektograph. 

Hektograph Ink. — Aniline color, 1 part; water, 7 
parts; glycerine, 1 part. A little alcohol may be 



AND THE MANIPULATION OF RUBBER. 151 

used with advantage to dissolve the aniline color. 
It can be expelled by heating if it proves objection- 
able. 

Aniline Ink Vehicle. — Prof. E. B. Shuttleworth, 
of Toronto, Ont., suggests the use of castor oil in 
place of vaseline and other vehicles for typewriter 
ink. The aniline colors may first be dissolved in 
alcohol, and the solution may be added to the oil. 
They may also be dissolved directly in the oil in 
which most of them are soluble. 

Indelible Stamping Inks. — I. Asphaltum, 1 part; 
oil of turpentine, 4 parts; dissolve and temper with 
printer's ink. The ink may be omitted, and solid 
dry color added. 

II. Sodium carbonate, 22 parts; glycerine, 85 
parts; dissolve and rub up in a mortar with gum 
arabic, 20 parts. In a separate vessel dissolve silver 
nitrate, 11 parts; in officinal aqua ammonia, 20 
parts. Mix the two solutions, and heat to the boil- 
ing point, 212° F. (100° C). After it darkens, add 
Venice turpentine, 10 parts. After applying to the 
cloth, a hot iron should be applied, or it should be 
exposed to the sun. 

III. Dr. W. Reissig's formula: 



Boiled linseed oil varnish 16 parts. 

Finest lamp black 6 " 

Ferric chloride (sesquichloride of 

iron) 2 to 5 " 



152 RUBBER HAND STAMP MAKING 

Dilute a little for use with varnish. After this 
ink has been removed, no matter how completely it 
can be detected by dipping the paper into a solution 
of ammonium sulphide. 

IV. 

Aniline black in crystals 1 part. 

Alcohol 30 f ' 

Glycerine 30 " 

Dissolve in the alcohol, and add the glycerine 
afterwards. 

Show Card Ink. — 

Pure asphaltum 16 parts. 

Venice turpentine 18 " 

Lamp-black 4 " 

Oil of turpentine 04 " 

Dissolve the asphaltum in the turpentine, and 
thoroughly mix. 

Stencil Ink. — Shellac, 2 ounces; borax, 2 ounces; 
water, 25 ounces. Dissolve by heat if necessary, 
first the borax alone, and then adding the shellac. 
To the clear solution add gum arabic, 2 ounces. 
Color with lamp-black, with Venetian red, or with 
ultramarine, to suit the taste. Another formula 
gives shellac, 4 parts, borax, 1 part, and omits the 
gum arabic. 

Copying Ink (for use without a press by simply 
pressing and rubbing with the hand), by Prof. Atfc- 
field, F.R. S. — Use ink of any kind of extra strength. 



AND THE MANIPULATION OF RUBBER. 153 

This in many cases can be made by evaporating 
common ink down to six tenths of its volume. 
Then mix with it two thirds of its volume of glycer- 
ine, so as to restore the original volume. 

White Ink. — Barium sulphate, or " flake white " 
is mixed with gum arabic water of sufficient thick- 
ness to keep it suspended, at least while in use. 
Starch or magnesium carbonate or other white pow- 
der may be used instead of the barium sulphate. 
The powder must be of impalpable fineness. 

White Ink on Blue Paper. — A solution of oxalic 
acid in water is used for this purpose. It may be 
applied with a rubber stamp or with a common pen. 
A quill or gold pen is the best as a steel pen is soon 
corroded. The ink bleaches the paper wherever it 
touches it, giving white lines on a blue ground. 

Gold Ink. — Gold leaf with honey is ground up in 
a mortar, best an agate mortar, or on a painters' 
slab with a muller. It is added to water, and thor- 
oughly mixed and at once poured off from the first 
sediments, filtered out, and washed. This is done to 
secure the impalpably finely ground gold only. 
The resulting powder is mixed with a suitable vehi' 
cle, such as white varnish or gum arabic water. 

Silver Ink. — As above, using silver leaf. 

Zinc Label Ink. — I. Verdigris, 1 part; ammo- 
nium chloride, 1 part; lamp-black, \ part; water, 10 
parts. 

II. Platinum bichloride, 1 part; gum arabic, 1 
part; water, 10 parts. 



154 RUBBER HAND STAMP MAKING 

Diamond Ink for Etching Glass. — This consists 
essentially of hydrofluoric acid mixed with barium 
sulphate to the consistency of cream. The barium 
sulphate is quite inoperative except as giving a body 
to prevent the ink from spreading. It is applied 
with a rubber stamp or pen and allowed to remain 
for ten minutes or until dry. On removal of the 
white powder, the design will be found etched on the 
glass. The following is a formula for it. 

Saturate hydrofluoric acid with ammonia, add an 
equal volume of hydrofluoric acid and thicken with 
barium sulphate in fine powder. 



CHAPTER XX. 

MISCELLANEOUS. 

To Soften and Restore India Rubber Hose, etc. — I. 
Dip in petroleum and hang up for a couple of days. 
Repeat process if necessary. 

II. The above process is applicable to all articles, 
but is specified for hose. It is stated that old rub- 
ber that has become hard may be softened by expos- 
ure first to vapor of carbon disulphide, followed by 
exposure to the vapor of kerosene. The latter vapor is 
found to be a general preservative for india rubber. 

III. Dr. Pol recommends immersion in a solution of 
water of ammonia, 1 part, and water 2 parts, from a 
few minutes to an hour. 

To Prevent Decay of Rubber Tubing.— -The decay 
of rubber tubing has been attributed to the forma- 
tion of sulphuric acid from the sulphur mixed 
with it. M. Ballard has suggested washing with 
water or weak alkaline solution five or six times in 
a year. 

Joints between India Rubber Tubing and Metal. — 
Where tubing is temporarily slipped over metal gas 
pipes and similar connections, as in the chemical lab- 
oratory, it is well to apply glycerine to the metal. 



156 RUBBER HAND STAMP MAKING 

It acts as a lubricant in slipping the tubing on, and 
assists in its withdrawal. 

Preserving Vulcanite. — Wash occasionally with a 
solution of ammonia and rub with a rag slightly 
moistened with kerosene oil. 

Effect of Copper upon Rubber. — In a paper read be- 
fore the recent meeting of the British Association, 
Sir William Thomson stated that metallic copper, 
when heated to the temperature of boiling water, in 
contact with the rubber, exerted a destructive effect 
upon it. With a view to finding whether this was 
due to the copper per se, or to its power of conduct- 
ing heat more rapidly to the rubber, he laid a sheet 
of rubber on a plate of glass, and on it placed four 
clean disks, one of copper, one of platinum, one of 
zinc and one of silver. After a few days in an incu- 
bator at 150° F., the rubber under the copper had be- 
come quite hard, that under the platinum had be- 
come slightly affected and hardened at different 
parts, while the rubber under the silver and under 
the zinc was quite hard and elastic. This would 
warrant the inference that the metallic copper had 
exerted a great oxidizing effect on the rubber, the 
platinum had exerted a slight effect, while the zinc 
and silver respectively had no injurious influence on 
it. The rubber thus hardened by the copper con- 
tained, strange enough, no appreciable trace of cop- 
per; the copper, therefore, presumably sets up the 
oxidizing action in the rubber without itself perme- 
ating it. 



AND THE MANIPULATION OF RUBBER. 157 

Gas Tight Tubings. — Fletcher has invented a gas 
tight rubber tubing in which a layer of tinfoil is in- 
terposed between two concentric rubber tubes, all 
vulcanized together. 

Printing Colors upon India Rubber. — It may some- 
times be desirable to have a surface of vulcanized in- 
dia rubber so prepared that it will take colors such as 
are used for calico printing. This end is simply at- 
tained by sprinkling the article with farina before 
vulcanizing. A small quantity attaches itself and 
forms an excellent base for color printing. 

Gutta-Percha for Coating Glass. — For focusing 
glass in photography and for similar purposes where 
ground glass or a translucent material is required, 
a solution of gutta-percha in chloroform is highly 
recommended. This is flowed over or painted on 
the glass and is allowed to evaporate afterwards. 

Burned Rubber. — A very soft pure gum sold for 
artists' use is improperly termed burned rubber. It 
is used in crayon work for removing and lightening 
marks by dabbing it against the paper, cleaning the 
rubber from time to time. It is so soft that it picks 
up and removes crayon marks without the necessity 
of friction. Thus the rubbing out or more properly 
erasing operation can be localized and crayon tints 
can be lightened in tone without impairment or 
"smutting." It is a very elegant accessory to the 
artists' paraphernalia. To make it, pure virgin gum, 
preferably the best Para, is cut into pieces and soaked 
for some hours in benzole. A long soaking is ad- 



158 RUBBER HAND STAMP MAKING 

visable. The pieces are then removed from the ben- 
zole and are ground in a mortar until perfectly hom- 
ogeneous. The mass is gathered up with a spatula 
and is pressed into little tin boxes. If desired it 
may be dried upon a water bath. This is not nec- 
essary as, if the box is left open, it will rapidly season 
itself. It should be very soft, should tend to adhere 
to the fingers, yet should leave them easily, and 
should strip cleanly from the box. A very little 
turpentine makes it more adhesive. It may even 
be softened in turpentine alone. This gives a gum 
that seasons more slowly and is in some respects pref- 
erable to the benzole made preparation. It is sold 
at a high price by the dealers, as the demand for it is 
limited. 

Rubier Sponge. — This is also an artist's rubber. 
It is also used for cleaning kid gloves. It is made 
by incorporating with the masticated or washed and 
sheeted gum any material or materials that will give 
off vapor in the curing process. Damp sawdust and 
crystallized alum are used as giving off vapor of 
water or steam, or ammonium carbonate as giving 
off vapors of ammonia carbonic acid gas and steam. 
The mixed gum may be cured in moulds, which it 
will fill by its expansion. 

Shellac Varnish for India Rubber. — This is made 
by soaking powdered shellac in ten times its weight 
of strong aqua ammonia (26° B.). At first no 
change beyond a coloring of the solution is percep- 
tible. After many days standing the bottle, which 



AND THE MANIPULATION OF RUBBER. 159 

should have a glass stopper, being tightly closed, 
the shellac disappears, having entered into solution. 
It may be a month before complete solution. This 
forms an excellent varnish for india rubber shoes 
and similar articles. It may be applied with a rag. 
It is also a good application for leather in some 
cases and doubtless many other uses could be 
made ot it. It would act well as a vehicle for a 
dark pigment such as lamp-black. It will reju- 
venate a pair of india rubbers very nicely. The 
ammonia exercises also a good influence on the rub- 
ber. It has been recommended as a cement for 
attaching rubber to metal, but its adhesive powers 
are not always satisfactory. 

Simple Substitute for Stamjjs. — A very simple 
though rough and imperfect substitute may be 
made by gluing with common carpenter's glue 
pieces of thick string upon a piece of wood, the 
string being given the form of the desired letters. 
Care must be taken to avoid saturating and stiffen- 
ing the string with the glue. 

India Rubber Substitutes. — One of these under 
the name of vulcanized oil is thus described by 
Bolas: 

" Vulcanized oil is, perhaps, of more interest, and 
many oils, such as linseed and others resembling it, 
may be vulcanized by being heated for some time to 
150° Centigrade with twelve to twenty per cent, of 
sulphur. The product obtained is soft, and some- 
what resembles very bad india rubber. By increas- 



160 RUBBER HAND STAMP MAKING 

ing the proportion of sulphur very much indeed, say 
to four times the weight of the oil, and vulcanizing 
at a higher temperature, a hard substance, resem- 
bling inferior vulcanite, is obtained. 

"Soft and hard vulcanized oil have been intro- 
duced into commerce at various, times and under 
many names; but these materials never seem to 
have made very much headway. " 

Another method of treating the oil consists in 
mixing it with a solution of chloride of sulphur in 
carbon disulphide or in naptha. On standing, the 
volatile solvents escape, leaving a thick mass, which 
is the substitute. 

In combinations of aluminum with the fatty 
acids, forming aluminum soaps, and of these, alu- 
minum palmitate especially, a substitute for india 
rubber has been sought but without success. 

Metallized Caoutchouc. — Unvulcanized gum is 
mixed with powdered lead, zinc, or antimony. The 
mixed india rubber is then cured as in the regular 
process. 

EMERY WHEELS AND WHETSTONES. 

Bolas thus describes their manufacture: 
" When ordinary vulcanized rubber is heated to 
230° Centigrade, (446° F.) or until it melts, a per- 
manently viscous product is obtained, and this sub- 
stance, if mixed with emery and sulphur to a kind 
of paste, forms a material out of which the so-called 
agglomerated emery wheels or grinders may be 



AND THE MANIPULATION OF RUBBER. 161 

formed, the mixed materials being next hardened or 
cured by the application of a steam heat. Emery 
wheels and hones made on this principle were intro- 
duced by Deplanque about twenty-three years ago. 

" Thirty-five parts of old vulcanized caoutchouc 
having been placed in a kind of still, heat is applied 
to melt it, the operation being assisted by the grad- 
ual addition of about ten parts of heavy coal oil; 
but this latter is afterward distilled off. The soft- 
ened caoutchouc is then incorporated with 500 parts 
of emery of the required degree of fineness and 
nine parts of sulphur. These materials having 
been thoroughly mixed, the hones or wheels are 
manufactured, and afterward cured or baked at a 
heat of 140° Centigrade, (284° F.) during a period of 
about eight hours. Grinding wheels, made in the 
above manner, can be worked at a speed of 2,000 
revolutions per minute, and are extremely useful 
for the working of hardened steel or other obdurate 
materials." 

Etching on Metals and Glass. — India rubber stamps 
can be used for placing the ground upon knife 
blades and similar articles which are to be etched. 
The parts untouched by the stamp are attacked by 
the acid. In the case of glass, diamond ink (page 
133) can be put on with a stamp. The acids for 
metal etching might be thickened with barium 
sulphate also and applied in the same way. In these 
cases the inscription of the stamp would be etched. 
Where ground is put on, whether on glass or 



162 RUBBER HAND STAMP MAKING 

metal, the design for the stamp will be pro- 
tected. 

Etching Ground for Metals. — Equal parts of as- 
phalt, Burgundy pitch and beeswax melted together 
and mixed thoroughly. It may be softened with 
mutton suet. Beeswax may be used, dissolved in 
ether or simply melted. Yellow soap is sufficient 
for ordinary work. 

Etching Solutions for Biting %n. — For steel and 
iron, a. sulphate of copper and common salt in solu- 
tion, b. sulphate of copper, sulphate of alumina, 
and common salt, of each two drachms; acetic 
acid, 1}4 oz. c. sulphuric acid, diluted with five vol- 
umes of water with a little sulphate of copper. 
For other metals, except gold and platinum, nitric 
acid diluted with five volumes of water. 

Etching Ground for Glass. — Melted beeswax is 
generally recommended. It can be removed with 
spirits of turpentine after as much as possible has 
been scraped off. 

Etching Glass. — Glass may be conveniently etched 
by exposing it to the vapor of hydrofluoric acid. 
A shallow leaden tray, as large as the glass, is re- 
quired. A quantity of fluorspar is placed in it and 
is moistened with concentrated sulphuric acid. The 
glass is placed face downward over the tray. It is 
supported over the mixture by resting on the 
edges of the tray or by any simple method, and the 
whole is covered with a towel. In half an hour or 
more the etching will be completed. The vapors 



AND THE MANIPULATION OF RUBBER. 163 

must not be allowed to escape into any room con- 
taining glass or metal articles as they corrode every- 
thing. Great care should be taken also not to let 
the mixture touch the hand, as painful ulcers are 
the result. 

India Rubber Shoe Blacking. — Raw india rubber 
is given as a constituent of several shoe blackings. 
Formulae are given as below for paste and liquid 
blackings. 

I. Paste blacking: bone-black, 20 parts; molasses, 
15 parts; vinegar, 4 parts; sulphuric acid, 4 parts; 
caoutchouc oil (as given below), 3 parts. 

II. Liquid blacking: bone-black, 60 parts; mo- 
lasses, 45 parts; gum arabic dissolved in water, 1 
part: vinegar, 50 parts; sulphuric acid, 24 parts; 
caoutchouc oil, 9 parts. 

Caoutchouc oil is made by dissolving or digesting 
virgin rubber 55 parts in linseed oil 450 parts. 

Waterproof Composition for Boots. — One ounce of 
virgin rubber cut into pieces is digested in enough 
oil of turpentine to form a stiff paste. In applying 
heat take great care lest the contents of the vessel 
become ignited. When homogeneous, which con- 
dition may be brought about by rubbing in a porce- 
lain mortar, as described in chapter XII., it is mixed 
with 5-6 ounces of boiled linseed oil. This gives 
an ointment almost of the consistency of butter. 



INDEX. 



TAGE 

Absorption of sulphur pro- 
cess 100 

Absorption of water by in- 
dia rubber 31 

Africa, ways of collecting 
rubber sap 15-17 

Analysis of sap of india rub- 
ber tree 27 

Apparatus for stamp mak- 
ing 61-63 

Artificial limbs 123 

Artificial teeth 124 

Artists' burned rubber . 157-158 

Balloon? 95 

Bands, india rubber 41 

Bicycle tire cement 146 

Blacking, india rubber 163 

Borax and water solution of 

rubber 106-107 

Brazil, ways of collecting 

sap 20-21 

Bromine as vulcanizer 100 

Bulbs, how made 92-93 

Burned rubber, artists'. 157-158 

Calendering 43 

Cane tips 90 

Caoutchin 30 

Caoutchoucin 30 

Caoutchouc (see India 
rubber). 

Cements 146-149 

Clamp for vulcanizing press 52 

Cleaning rubber goods 138 

Cohesion of rubber, its im- 
portance to the manufac- 
turer 26-27 

Cold curing 100-102 

Composition for stamps and 

its moulding 1 13-120 

Composition inking pad.l 1 8-119 
Composition stamp handle . 
117-118 



PAGE 

Cord, rubber 92 

Corks 90-91 

Curing 44 

Curing, how to judge of 

completion of 70 

Curing in liquid bath 97 

Curing in sulphur bath. ... 99 
Curing, temperature of . . . . 58 
Central America, ways of 

collecting rubber 18-19 

Chair leg tips 90 

Chalk plates 83-84 

Chlorine as vulcanizer 100 

Chloroform as a solvent .... 105 
Coagulation of sap by a 

plant 19 

Coagulation of sap by alum. 

22-23 
Coagulation of sap by fire 21-22 
Coagulation of sap by salt . . 18 
Cohesion of pure rubber .... 25 

Dating stamps, composi- 
tion 116-117 

Didot's polytype for ma- 
trices 82-83 

Distillation products of in- 
dia rubber 29-30 

Dolls, how made 92-93 

Ebonite 108-111 

Ebonite, polishing 110-111 

Emery wheels and whet- 
stones 160-161 

Emulsion of caoutchouc. ... 10 
Etching 140-163 

Fins, removal of 86 

Flask for type moulding .... 74 

Flong matrices 80-82 

Flong paste 80 

Fluid for mixing with plas- 
ter for matrices 55 

Gas heated steam vulcanizer 53 



INDEX. 



165 



Glue, marine 126 

Glue stamps 113-120 

Glycerine bath for curing . . 97 

Goodyear, Charles 13-14 

Gutta-percha 111-112 

G u tt a-percha , moulding. 

111-112 
Gutta-percha, vulcanizing . Ill 

Hektograph, composition. 

142, 143. 144 
Hektograph, how made and 

used 142-144 

Hektograph ink (also see 

inks) 142 

Hektograph sheets 145 

India Rubber, absorption 
of water by 31 

India rubber, African. . . . 15-17 

India rubber, artists' 
burned 157-158 

India rubber, availability 
for small articles 85 

India rubber, cohesion of 
unvulcanized 25 

India rubber, composition 
of 27 

India rubber, discovery of, 
etc 11-13 

India rubber, effects of tem- 
perature on 28-29 

India rubber, elasticity of 28—29 

India rubber sap, its coagu- 
lation 11 

India rubber sheet, how 
made 40 

India rubbers, original way 
of making 10 

India rubber stamp making 

without apparatus 71 

India rubber stamps, home- 
made mould 48-50 

India rubber stamps, start- 
ing point 47 



India rubber, trees produc- 
ing 9 

India rubber tree sap, 
analysis of 27 

India rubber type 73 

India rubber, vulcanized, 
general properties of . . . 32-33 

India rubber, where col- 
lected 11 

India rubber, nelastic, how 
made 31 

India rubber, its mastica- 
tion 38-40 

India rubber, manufacture 
of 35-46 

India rubber, necessity of 
drying 38 

India rubber, points to be 
followed in moulding 
small articles 85 

India rubber, preliminary 
operations in manufac- 
turing 35-36 

India rubber, preserving, 
etc 155-156 

India rubber, properties of . 28 

India rubber sap 9-11 

India rubber stamp vulcan- 
izing 58-60 

Inelastic state of india rub- 
ber 31 

Inks, special for stamping, 
etc 150-154 

Inner tube 129 

Iodine and haloid vulcan- 
izers 100 

Isoprene 30 

"Kerite" 140 

Leaves, skeletonized as 

models 92 

Liquid bath curing 97 

Machine for cutting sheet 
and threads 40 



1G6 



INDEX. 



Machine for making mixed 

sheet 42-43 

Machine for masticating . 38-40 
Machine for washing and 

sheeting 37 

Mackintosh 13 

Mackintoshes, how made. 45-46 
Marshmallow not for mix- 
ture with plaster 57 

Masticated rubber, its easy 

solution 103-104 

Masticating in mortar with 

benzole 103-104 

Mastication of rubber. . . 38-40 
Materials mixed with india 

rubber 43 

Matrices, various kinds of, 

for stamps 80-84 

Matrix for stamp-making. 

54-55 
Matrix making by casting. 

56-57 

Matrix press 56 

Matrix, process of making, 

for stamps 54-55 

Mats 91-92 

Metals, welding and cohes- 
ion of 25-26 

Miscellaneous 155-163 

Mixed sheet 42-44 

Mixed sheet for stamps . . 47-48 
Mould, home-made for 

stamps 48-50 

Moulding and curing 

stamps 58-60 

Moulds for composition 

stamps, temperature of. . 120 
Moulds, material for 86 

Naphtha and volatile solv- 
ents, danger of 107 

Naphtha, solvent 104-105 

Nicaragua, ways of collect- 
ing sap 19-20 

Nitric acid as vulcanizer. . . 100 



Oil for composition stamp 
moulds 119-120 

Oil for mould face 55 

Oils, fixed, bad effect on 
solutions 105 

Oxychloride of zinc cement 
for matrices 57 

Papier macho matrices . . 80-82 
Paraffin and rubber. . . 105-106 

Parkes' process 100-102 

Payen's solvent 105 

Pencil tips, moulds for. . . 89-90 
Phenyle sulphide as softener 

of vulcanized rubber. . . . 106 
Plaster dental for matrices . 54 
Press for moulding stamps, 

etc 51-52 

Press, gas-heated 52-53 

Press, home-made 49 

Press, matrix making .... 55-56 
Products, general division 

of 35-36 

Repairing tires 133 

Rods, stirring for labora- 
tory 95 

Rubber in surgery and 

dentistry 121 

Rubber, origin of name 12 

Rubber (see India rubber) . 
Rubber tires 127 

Salt bath for curing 98 

Sap of india rubber tree, 

analysis of 27 

Sheeting and washing .... 37-38 
Sheet rubber, how made ... 40 
Sheet rubber, its joining ... 94 
Shellac for strengthening 

matrix 55 

Shoes blacking for 163 

Shoes, india rubber, cement 

for 148 

Siphonia, origin of name. . . 11 



INDEX. 



167 



Solution, different views of 

31-32 

Solution, difficulties of 103 

Solvents for rubber .... 104-105 
Spring chase for matrices. . . 56 
Springs for stamp moulds. . 51 
Springs on moulding press. 51 

Sponge india rubber 158 

Stamp making 47 

Stamps, rubber, substitute 

for 159 

Stamps (see India rubber, 
Composition and general 
titles). 
Strauss' method of coagu- 
lating sap 22-23 

Suction discs, regular mould 

for 88-89 

Suction discs, simple mould 

for 87-88 

Sulphides, alkaline as vul- 

canizers 100 

Sulphur, absorption pro- 
cess 100 

Sulphur bath for mixing and 

curing 98-100 

Sulphur chloride process . 

100-102 
Sulphur, how mixed with 

gum 43 

Sulphur, its escape from 

vulcanized rubber 33-34 

Sunlight excluded from 

washed sheet rubber 38 

Syringes made by Indians . . 11 

Test for curing with knife. 48 

Thread, rubber, cut 41 

Thread, rubber moulded. . . 92 

Tire construction 130-132 

Tires, rubber 127 

Tissues, coated, how made. 

45-46 
Tubes, connecting glass. ... 96 
Tube, seamless 92 



Turpentine, a solvent for 

vulcanized rubber 10Q 

Turpentine compared with 

caoutchoucin 30 

Turpentine, viscid nature of 

solution 104-105 

Type, india rubber 73 

Type moulding flask 74 

Type and stamps from vul- 
canized rubber 77 

Type, cutting apart 75 

Type, points in moulding. . 75 
Type, quads, and spaces for 

stamp models 71-72 

Type, steel moulds for 76 

United States composition 
stamps 113-120 

Varnish shellac for india 

rubber 158-159 

Vulcanite 108-111 

Vulcanization, its two steps. 42 
Vulcanization, steps in pro- 
cess 47-48 

Vulcanized rubber stamps 

and type 77 

Vulcanizer 52-53 

Vulcanizer, chamber 63 

Vulcanizer, fish kettle as a . 

69-70 
Vulcanizer, flower pot. . . 68-70 
Vulcanizing and moulding 
stamps 58-60 

Washing and sheeting. . 37-38 
Water absorbed by india 

rubber 31 

Waterproof composition for 

shoes 163 

Waterproofing for battery 

cells 148-149 

Zinc chloride 57 



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Receipt Book 24 

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velopments of the industry. 

Contents: Chap. I. Introductory. Chap. II. General Classi- 
fication of Fuels. Chap. III. Coal Washing. Chap. IV. The 
Sampling and Valuation of Coal, Coke, etc. Chap. V. The 
Calorific Power of Coal and Coke. Chap. VI. Coke Ovens. 
Chap. VII. Coke Ovens, continued. Chap. VIII. Coke Ovens, 
continued. Chap. IX. Charging and Discharging of Coke Ovens. 
Chap. X. Cooling and Condensing Plant. Chap. XL Gas Ex- 
hausters. Chap. XII. Composition and Analysis of Ammoniacal 
Liquor. Chap. XIII. Working up of Ammoniacal Liquor. 
Chap. XIV. Treatment of Waste Gases from Sulphate Plants. 
Chap. XV. Valuation of Ammonium Sulphate. Chap. XVI. 
Direct Recovery of Ammonia from Coke Oven Gases. Chap. 
XVII. Surplus Gas from Coke Oven. Useful Tables. Very 
fully illustrated. 83.50 net 

COMPRESSED AIR 



COMPRESSED AIR IN ALL ITS APPLICATIONS. By 

Gardner D. Hiscox. This is the most complete book on the 
subject of Air that has ever been issued, and its thirty-five 
chapters include about every phase of the subject one can think 
of. It may be called an encyclopedia of compressed air. It is 
written by an expert, who, in its 665 pages, has dealt with the 
subject in a comprehensive manner, no phase of it being omitted. 
Over 500 illustrations, 5th Edition, revised and enlarged. 
Cloth bound; 85.00, Half morocco, 86.5tt 



CONCRETE 



ORNAMENTAL, CONCRETE WITHOUT MOLDS, By A. A. 

Houghton. The process for making ornamental concrete with- 
out molds, has lonj been held as a secret and now, for the first 
time, this process is given to the public. The book reveals the 
secret and is the only book published which explains a simple, 
practical method whereby the concrete worker is enabled, by 
employing wood and metal templates of different designs, to 
mold or model in concrete any Cornice, Archivolt, Column, 
Pedestal, Base Cap, Urn or Pier in a monolithic form — right 
upon the job. These may be molded in units or blocks, and 
then built up to suit the specifications demanded. This work 
is fully illustrated, with detailed engravings. $2.00 

POPULAR HAND BOOK FOR CEMENT AND CON- 
CRETE USERS, By Myron H. Lewis, C.E. This is a con- 
cise treatise of the principles and methods employed in the 
manufacture and use of cement in all classes of modern works. 
The author has brought together in this work, all the salient 
matter of interest to the user of concrete and its many diversified 
products. The matter is presented in logical and systematic 
order, clearly written, fully illustrated and free from involved 
mathematics. Everything of value to the concrete user is given. 
Among the chapters contained in the book are: I. Historical 
Development of the Uses of Cement and Concrete. II. Glossary 
of Terms employed in Cement and Concrete work. III. Kinds 
of Cement employed in Construction. IV. Limes, Ordinary and 
Hydraulic. V. Lime Plasters. VI. Natural Cements. VII. 
Portland Cements. VIII. Inspection and Testing. IX. Adul- 
teration; or Foreign Substances in Cement. X. Sand, Gravel 
and Broken Stone. XL Mortar. XII. Grout. XIII. Con- 
crete (Plain). XIV. Concrete (Reinforced,). XV. Methods 
and Kinds of Reinforcements. XVl. Forms for Plain and Re- 
inforced Concrete. XVII. Concrete Blocks. XVIII. Arti- 
ficial Stone. XIX. Concrete Tiles. XX. Concrete Pipes and 
Conduits. XXI. Concrete Piles. XXII. Concrete Buildings. 
XXIII. Concrete in Water Works. XXIV. Concrete in Sewer 
Works. XXV. Concrete in Highway Construction. XXVI. 
Concrete Retaining Walls. XXVII. Concrete Arches and 
Abutments. XXVIII. Concrete in Subway and Tunnels. 
XXIX. Concrete in Bridge Work. XXX. Concrete in Docks 
and Wharves. XXXI. Concrete Construction under Water. 
XXXII. Concrete on the Farm. XXXIII. Concrete Chimneys. 
XXXIV. Concrete for Ornamentation. XXXV. Concrete 
Mausoleums and Miscellaneous Uses. XXXVI. Inspection for 
Concrete Work. XXX VI I. Waterproofing Concrete Work. 
XXXVIII. Coloring and Painting Concrete Work. XXXIX. 
Method of Finishing Concrete Surfaces. XL. Specifications and 
Estimates for Concrete Work. S'2.50 

DICTIONARIES 



STANDARD ELECTKICAL DICTIONARY. By T. 

O'Conor Sloane. An indispensable work to all interested in 
electrical science. Suitable alike for the student and profession- 
al. A practical hand-book of reference containing definitions 
of about 5,000 distinct words, terms and phrases. The defini- 
tions are terse and concise and include every term used in electri- 
cal science. Recently issued. An entirely new edition. Should 
be in the possession of all who desire to keep jbreast with the 
progress of this branch of science. Complete tcnciss and con- 
venient. 682pr?es — 393 illustrations. S3.G0 



DIE S— METAL WORK 

DIBS. THEIR CONSTRUCTION AND USE FOR THE 
MODERN WORKING OF SHEET METALS. By J. V. 

Woodworth. A new book by a practical man, for those who. 
wish to know the latest practice in the working of sheet metals. 
It shows how dies are designed, made and used, and those who 
are engaged in this line of work can secure many valuable sug- 
gestions. $3.00 

PUNCHES, DIES AND TOOLS FOR MANUFACTUR- 
ING IN PRESSES. By J. V. Woodworth. An encyclo- 
pedia of die-making, punch-making, die-sinking, sheet-metal 
working, and making of special tools, subpresses, devices and 
mechanical combinations for punching, cutting, bending, form- 
ing, piercing, drawing, compressing, and assembling sheet- 
metal parts and also articles of other materials in machine 
tools. This is a distinct work from the author's book entitled 
"Dies; Their Construction and Use." 500 pages, 700 engrav- 
ings. $4.00 

DRAWING— SKETCHING PAPER 



LINEAR PERSPECTIVE SELF-TAUGHT. By Herman 
T. C. Kraus. This work gives the theory and practice of linear 
perspective, as used in architectural, engineering, and mechanical 
drawings. Persons taking up the study of the subject by them- 
selves, without the aid of a teacher, will be able by the use of the 
instruction given to readily grasp the subject, and by reason- 
able practice become good perspective draftsmen. The arrange- 
ment of the book is good; the plate is on the left-hand, while the 
descriptive text follows on the opposite page, so as to be readily 
referred to. The drawings are on sufficiently large scale to show 
the work clearly and are plainly figured. The whole work makes. 
a very complete course on perspective drawing, and will be 
found of great value to architects, civil and mechanical engineers, 
patent attorneys, art designers, engravers, and draftsmen. $2.50 

PRACTICAL PERSPECTIVE. By Richards and Colvin. 
Shows just how to make all kinds of mechanical drawings in the 
only practical perspective isometric. Makes everything plain 
so that any mechanic can understand a sketch or drawing in 
this way. Saves time in the drawing room and mistakes in the 
shops. Contains practical examples of various classes of work. 

50 tents 

SELF-TAUGHT MECHANICAL DRAWING AND ELE- 
MENTARY MACHINE DESIGN. By F. L. Sylvesj er, M.E., 
Draftsman, with additions by Erik Oberg, associate editor of 
"Machinery." A practical elementary treatise on Mechanical 
Drawing and Machine Design, comprising the first principles of 
geometric and mechanical drawing, workshop mathematics, 
mechanics, strength of materials and the calculation and design 
of machine details, compiled for the use of practical mechanics 
and young draftsmen. S3. 00' 

A NEW SKETCHING PAPER. A new specially ruled paper 
to enable you to make sketches or drawings in isometric per- 
spective without any figuring or fussing. It is being used for 
shop details as well as for assembly drawings, as it makes one 
sketch do the work of three, and no workman can help seeing 
just what is wanted. Pads of 40 sheets 6x9 inches, 25 cents. 
Pads of 40 sheets, 9x12 inches, 50 cent* 



ELECTRICITY 



ARITHMETIC OF ELECTRICITY. By Prof. T. O'Conor 
Sloane. A practical treatise on electrical calculations of alJ 
kinds reduced to a series of rules, all of the simplest forms, and 
involving only ordinary arithmetic; each rule illustrated by 
one or more practical problems, with detailed solution of each 
one. This book is classed among the most useful works pub- 
lished on the science of electricity covering as it does the mathe- 
matics of electricity in a manner that will attract the attention 
of those who are not familiar with algebraical formulas. 160 
pages. S1.0C- 

COMMUTATOR CONSTRUCTION. By Wm. Baxter, 
Jr. The business end of any dynamo or motor of the direct 
current type is the commutator. This book goes into the de- 
signing, building, and maintenance of commutators, shows 
how to locate troubles and how to remedy them; everyone who 
fusses with dynamos needs this. 25 cents 

DYNAMO BUILDING FOR AMATEURS, OR HOW TO 
CONSTRUCT A FIFTY WATT DYNAMO. By Arthur 
J. Weed, Member of N. Y. Electrical Society. This book is a 
practical treatise showing in detail the construction of a small 
dynamo or motor, the entire machine work of which can be done 
on a small foot lathe. 

Dimensioned working drawings are given for each piece of 
machine work and each operation is clearly described. 

This machine when used as a dynamo has an output of fifty 
watts; when used as a motor it will drive a small drill press or 
lathe. It can be used to drive a sewing machine on any and all' 
ordinary work. 

The book is illustrated with more than sixty original engrav- 
ings showing the actual construction of the different parts. Paper. 

Paper 50 cents Cloth SI -CO 

ELECTRIC FURNACES AND THEIR INDUSTRIAL 
APPLICATIONS. By J. Wright. This is a book which will 
prove of interest to many classes of people; the manufacturer 
who desires to know what product can be manufactured success- 
fully in the electric furnace, the chemist who wishes to post 
himself on the electro-chemistry, and the student of science 
who merely looks into the subject from curiosity. 2 88 pages. 

$3.00 

ELECTRIC LIGHTING AND HEATING POCKET 

BOOK. By Sydney F. Walker. This book puts in conven- 
ient form useful information regarding the apparatus which is 
likely to be attached to the mains of an electrical company. 
Tables of units and equivalents are included and useful electrical 
laws and formulas are stated. 438 pages, 300 engravings. S3.00 

ELECTRIC TOY MAKING, DYNAMO BUILDING, AM) 
ELECTRIC MOTOR CONSTRUCTION. This work treats 
of the making at home of electrical toys, electrical apparatus, 
motors, dynamos, and instruments in general, and is designed to- 
bring within the reach of young and old the manufacture of gen- 
uine and upefuJ electrical appliances. 185 pages. Fully illus- 
trated. S1.0*- 



ELECTRIC WIRING, DIAGRAMS AND SWITCH- 
BOARDS. By Newton Harrison. This is the only complete 
work issued showing and telling you what you should know 
about direct and alternating current wiring. It is a ready 
reference. The work is free from advanced technicalities and 
mathematics. Arithmetic being used throughout. It is in every 
respect a handy, well-written, instructive, comprehensive 
volume on wiring for the wireman, foreman, contractor or elec- 
trician. 272 pages, 105 illustrations. $1.60 

ELECTRICIAN'S HANDY BOOK. By Prof. T. O'Conor 
Sloane. This work is intended for the practical electrician, 
who has to make things go. The entire field of Electricity is 
covered within its pages. It contains no useless theory; every- 
thing is to the point. It teaches you just what you should 
know about electricity. It is the standard work published on 
the subject. Forty-one chapters, 610 engravings, handsomely 
bound in red leather with titles and edges in gold. $3.50 

ELECTRICITY IN FACTORIES AND WORKSHOPS. 
ITS COST AND CONVENIENCE. By Arthur P. Haslam. 
A practical book for power producers and power users showing 
what a convenience the electric motor, in its various forms, has 
become to the modern manufacturer. It also deals with the 
conditions which determine the cost of electric driving, and 
compares this with other methods of producing and utn'ing 
power. 312 pages. Very fully illustrated. $&. 50 

ELECTRICITY SIMPLIFIED. By Prof. T. O'Conor 
Sloane. The object of "Electricity Simplified" is to make the 
subject as plain as possible and to show what the modern con- 
ception of electricity is; to show how two plates of different 
metals immersed in acid can send a message around the globe; 
to explain how a bundle of copper wire rotated by a steam engine 
can be the agent in lighting our streets, to tell what the volt, ohm 
and ampere are, and what high and low tension mean; and to 
answer the questions that perpetually arise in the mind in this 
age of electricity. 172 pages. Illustrated. $1.00 

HOW TO BECOME A SUCCESSFUL ELECTRICIAN. 

By Prof. T. O'Conor Sloane. An interesting book from cover 
to cover. Telling in simplest language the surest and easiest way 
to become a successful electrician. The studies to be followed, 
methods of work, field of operation and the requirements of the 
successful electrician are pointed out and fully explained. 
202 pages. Illustrated. $1.00 

MANAGEMENT OF DYNAMOS. By Lummis-Pater- 
son. A handbook of theory and practice. This work is arranged 
in three parts. The first part covers the elementary theory of 
the dynamo. The second part, the construction and action of 
the different classes of dynamos in common use are described; 
while the third part relates to such matters as affect the prac- 
tical management and working of dynamos and motors. 292 
pages, 117 illustrations. $1.50 

STANDARD ELECTRICAL DICTIONARY. By Prof. T. 
O'Conor Sloane. A practical handbook of reference contain- 
ing definitions of about 5,000 distinct words, terms and phrases. 
The definitions a»e terse and concise and include every term 
used in electrical science. 682 pages, 393 illustrations. $3.00 

8 



SWITCHBOARDS. By William Baxter, Jr. This book 
appeals to every engineer and electrician who wants to know 
the practical side of things. All sorts and conditions of dynamos, 
connections and circuits are shown by diagram and illustrate 
just how the switchboard should be connected. Includes direct 
and alternating current boards, also those for arc lighting, in- 
candescent, and power circuits. Special treatment on high 
voltage boards for power transmission. 190 pages. Illustrated. 

81.50 

TELEPHONE CONSTRUCTION, INSTALLATION, 
WIRING, OPERATION AND MAINTENANCE. By W. H. 

Radcliffe and H. C. Cushing. This book gives the principles 
of construction and operation of both the Bell and Independent 
instruments; approved methods of installing and wiring them; 
the means of protecting them from lightning and abnormal cur- 
rents; their connection together for operation as series or bridg- 
ing stations; and rules for their inspection and maintenance. 
Line wiring and the wiring and operation of special telephone 
systems are also treated. 180 pages, 125 illustrations. $1.00 

WIRING A HOUSE. By Herbert Pratt. Shows a house 
already built; tells just how to start about wiring it. Where to 
begin; what wire to use; how to run it according to insurance 
rules, in fact just the information you need. Directions apply 
equally to a shop. Fourth edition. 25 cents 

WIRELESS TELEPHONES AND HOW THEY WORK. 

By James Erskine-Murray. This work is free from elaborate 
details and aims at giving a clear survey of the way in which 
Wireless Telephones work. It is intended for amateur workers 
and for those whose knowledge of Electricity is slight. Chap- 
ters contained: How We Hear — Historical — The Conversion of 
Sound into Electric Waves — Wireless Transmission — The Pro- 
duction of Alternating Currents of High Frequency — How the 
Electric Waves are Radiated and Received — The Receiving 
Instruments — Detectors — Achievements and Expectations — 
Glossary of Technical Work. Cloth. »1.00 



ENAMELING 



HENLEY'S TWENTIETH CENTURY RECEIPT BOOK. 

Edited by Gardner D. Hiscox. A work of 10,000 practical 
receipts, including enameling receipts for hollow ware, for 
metals, for signs, for china and porcelain, for wood, etc Thor- 
ough and practical. See page 24 for full description of this book. 

S3.00 

FACTORY MANAGEMENT, ETC. 



MODERN MACHINE SHOP CONSTRUCTION, EQUIP- 
MENT AND MANAGEMENT. By 0. E. Perrigo, M.E. A 
work designed for the practical and every-day use of the Archi- 
tect who designs, the Manufacturers who build, the Engineers 
who plan and equip, the Superintendents who organize and 
direct, and for the information of every stockholder, director, 
officer, accountant, clerk, superintendent, foreman, and work- 
man of the modern machine shop and manufacturing plant of 
Industrial America. $5.00 



FUEL 

COMBUSTION OF COAL AND THE PREVENTION 
OF SMOKE. By Wm. M. Barr. To be a success a firemaa 
must be "Light on Coal." He must keep his fire in good con- 
dition, and prevent, as far as possible, the smoke nuisance. 
To do this, he should know how coal burns, how smoke is formed 
and the proper burning of fuel to obtain the best results. He 
can learn this, and more too, from Barr's "Combustion of Coal." 
It is an absolute axithority on all questions relating to the Firing 
of a Locomotive. Nearly 350 pages, fully illustrated. $1.00 

SMOKE PREVENTION AND FUEL ECONOMY. By 

Booth and Kershaw. As the title indicates, this book of 197 
pages and 75 illustrations deals with the problem of complete- 
combustion, which it treats from the chemical and mechanical 
standpoints, besides pointing out the economical and humani- 
tarian aspects of the question. $2.50 



GAS ENGINES AND GAS 



CHEMISTRY OF GAS MANUFACTURE. By H. M. 

Royles. A practical treatise for the use of gas engineers, gas 
managers and students. Including among its contents — Prepa- 
rations of Standard Solutions, Coal, Furnaces, Testing and 
Regulation. Products of Carbonization. Analysis of Crude Coal 
Gas. Analysis of Lime. Ammonia. Analysis of Oxide of Iron. 
Naphthalene. Analysis of Fire-Bricks and Fire-Clay. Weldom 
«md Spent Oxide. Photometry and Gas Testing. Carbur- 
etted Water Gas. Metrooolis Gas. Miscellaneous Extracts. 
Useful Tables. $4.50 

GAS ENGINE CONSTRUCTION, Or How to Build a Half- 
Horse-power Gas Engine. By Parsell and Weed. A prac- 
tical treatise describing the theory and principles of the action of 
gas engines of various types, and the design and construction of a 
half-horse-power gas engine, with illustrations of the work in 
actual progress, together with dimensioned working drawings giv- 
ing clearly the sizes of the various details. 3 co pages. $2.50 

GAS, GASOLINE, AND OILENGINES. By Gardner D. 

Hiscox. Just issued, 18th revised and enlarged edition. Every 
user of a gas engine needs this book. Simple, instructive, and 
right up-to-date. The only complete, work on the subject. Tells 
all about the running and management of gas, gasoline and oil 
engines as designed and manufactured in the United States. 
Explosive motors for stationary, marine and vehicle power are 
fully treated, together with illustrations of their parts and tabu- 
lated sizes, also their care and running are included. Electric 
Ignition by Induction Coil and Jump Sparks are fully explained 
and illustrated, including valuable information on the testing for 
economy and power and the erection of power plants. 

The special information on producer and suction gases in- 
cluded cannot fail to prove of value to all_ interested in the gen- 
eration of producer gas and its utilization in gas engines. 

The rules and regulations of the Board of Fire Underwriters 
in regard to the installation and management of Gasoline Motors 
is given in fulT, suggesting the safe installation of explosive motor 
power. A list of United States Patents issued on Gas, Gasoline 
and Oil Engines and their adjuncts from 1875 to date is included. 
484 pages. 410 engravings. $3.50 net 



MODERN GAS ENGINES AND PRODUCER GAS 
PLANTS. By R. E. Mathot, M.E. A practical treatise ot 
320 pages, fully illustrated by 175 detailed illustrations, setting 
forth the principles of gas engines and producer design, the selec- 
tion and installation of an engine, conditions of perfect opera- 
tion, producer-gas engines and their possibilities, the care of gaa 
engines and producer-gas plants, with a chapter on volatile 
hydrocarbon and oil engines. This book has been endorsed by 
JJugal Clerk as a most useful work for all interested in Gas Engine 
installation and Producer Gas. 83.50- 

GEARING AND CA IS 



BEVEL GEAR TABLES. By D. Ac. Engstrom. No one 
who has to do with bevel gears in any way should be without 
this book. The designer and draftsman will find it a great con- 
venience, while to the machinist who turns up the blanks or cuts 
the teeth, it is invaluable, as all needed dimensions are given 
and no fancy figuring need be done. $1.00 

CHANGE GEAR DEVICES. By Oscar E. Perrioo. A 
book for every designer, draftsman and mechanic who is inter- 
ested in feed changes for any kind of machines. This shows what 
has been done and how. Gives plans, patents and all information 
that you need. Saves hunting through patent records and rein- 
venting old ideas. A standard work of reference. 81.00' 

DRAFTING OF CAMS. By Louis Rouillion. The 
laying out of cams is a serious problem unless you know how to 
go at it right. This puts you on the right road for practically 
any kind of cam you are likely to run up against. 35 cents 

HYDRAULICS 



HYDRAULIC ENGINEERING. By Gardner D. Hiscox. 
A treatise on the properties, power, and resources of water for all 
purposes. Including the measurement of streams; the flow of 
water in pipes or conduits; the horse-power of falling water- 
turbine and impact water-wheels; wave-motors, centrifugal' 
reciprocating, and air-lift pumps. With 300 figures and dia- 
grams and 36 practical tables. 320 pages. 84.00 



ICE AND REFRIGERATION 



POCKET BOOK OF REFRIGERATION AND ICE MAK- 
ING, By A. J. Wallis-Taylor. This is one of the latest and' 
most comprehensive reference books published on the subject 
of refrigeration and cold storage. It explains the properties and 
refrigerating effect of the different fluids in use, the manage- 
ment of refrigerating machinery and the construction and insula- 
tion of cold rooms with their required pipe surface for different 
degrees of cold; freezing mixtures and non-freezing brines 
temperatures of cold rooms for all kinds of provisions cold 
storage charges for all classes of goods, ice making and storage of 
ice, data and memoranda for constant reference bv refrigerating 
engineers, with nearly one hundred tables containing valuable 
references to every fact and condition required in the installment 
and operation of a refrigerating plant. 81.50 



II 



INVENTIONS— PATENTb 



INVENTOR'S MANUAL, HOW TO MAKE A PATENT 
PAY. This is a book designed as a guide to inventors in per- 
fecting their inventions, taking out their patents, and disposing 
of them. It is not in any sense a Patent Solicitor's Circular, 
nor a Patent Broker's Advertisement. No advertisements of any 
description appear in the work. It is a book containing a quartet 
of a century's experience of a successful inventor, together with 
notes based upon the experience of many other inventors. $1.00 

LATHE PRACTICE 



MODERN AMERICAN LATHE PRACTICE. By Oscar 
E. Perrigo. An up-to-date book on American Lathe Work, 
describing and illustrating the very latest practice in lathe and 
boring-mill operations, as well as the construction of and latest 
developments in the manufacture of these important classes of 
machine tools. 300 pages, fully illustrated. $'4.50 

PRACTICAL, METAL TURNING. By Joseph G. Horner. 
A work of 404 pages, fully illustrated, covering in a comprehen- 
sive manner the modern practice of machining metal parts in 
the lathe, including the regular engine lathe, its essential design, 
its uses, its tools, its attachments, and the manner of holding the 
work and performing the operations. The modernized engine 
lathe, its methods, tools, and great range of accurate work. The 
Turret Lathe, its tools, accessories and methods of performing 
its functions. Chapters on special work, grinding, tool holders, 
speeds, feeds, modern tool steels, etc., etc. $3.50 

TURNING AND BORING TAPERS. By Fred H. Col- 
vin. There are two ways to turn tapers; the right way and 
one other. This treatise has to do with the right way; it tells 
you how to start the work properly, how to set the lathe, what 
tools to use and how to use them, and forty and one other little 
things that you should know. Fourth edition. 25 cents 

LIQUID AIR 

LIQUID AIR AND THE LIQUEFACTION OF GASES. 

By T. O'Conor Sloane. Theory, history, biography, practical 
applications, manufacture. 365 pages. Illustrated. $2.00 

LOCOMOTIVE ENGINEERING 



AIR-BRAKE CATECHISM. By Robert H. Blackall. 
This book is a standard text book. It covers the Westinghouse 
Air-Brake Equipment, including the No. 5 and the No. 6 E T 
Locomotive Brake Equipment; the K (Quick-Service) Triple 
Valve for Freight Service; and the Cross-Compound Pump. 
The operation of all parts of the apparatus is explained in detail, 
and a practical way of finding their peculiarities and defects, 
with a proper remedy, is given. It contains 2,000 questions with 
their answers, which will enable any railroad man to pass any 
examination on the subject of Air Brakes. Endorsed and used 
by air-brake instructors and examiners on nearly every rail- 
road in the United States. 23d Edition. 380 pages, fully 
illustrated with folding plates ^nd diagrams. $2.00 

12 



AMERICAN COMPOUND LOCOMOTIVES. By Fred 

H. Colvix. The most complete book on compounds published. 
Shows all types, including the balanced compound. Makes 
everything clear by many illustrations, and shows valve setting, 
breakdowns and repairs. 142 pages. 81. 00 

APPLICATION OF HIGHLY SUPERHEATED STEAM 
TO LOCOMOTIVES. By Robert Garbe. A practical book. 
Contains special chapters on Generation of Highly Superheated 
Steam; Superheated Steam and the Two-Cylinder Simple 
Engine; Compounding and Superheating; Designs of Locomotive 
Superheaters; Constructive Details of Locomotives using Highly 
Superheated Steam; Experimental and "Working Results. Illus- 
trated with folding plates and tables. $2.50 

COMBUSTION OF COAL AND THE PREVENTION 
OF SMOKE. By Wm. M. Barr. To be a success a fireman 
must be " Light on Coal." He must keep his fire in good con- 
dition, and prevent as far as possible, the smoke nuisance. 
To do this, he should know how coal burns, how smoke is formed 
and the proper burning of fuel to obtain the best results. He 
can learn this, and more too, from Barr's "Combination of Coal." 
It is an absolute authority on all questions relating to the Firing 
of a Locomotive. Nearly 350 pages, fully illustrated. $1.00 

LINK MOTIONS, VALVES AND VALVE SETTING. By 

Fred H. Colvin, Associate Editor of "American Machinist." 
A handy book that clears up the mysteries of valve setting. 
Shows the different valve gears in use, how they work, and why. 
Piston and slide valves of different types are illustrated and 
explained. A book that every railroad man in the motive- 
power department ought to have. Fully illustrated. 50 cents. 

LOCOMOTIVE BOILER CONSTRUCTION. By Frank 

A. Kleinhans. _ The only book showing how locomotive 
boilers are built in modern shops. Shows all types of boilers 
used; gives details of construction; practical facts, such as 
life of riveting punches and dies, work done per day, allowance 
for bending and flanging sheets and other data that means dol- 
lars to any railroad man. 421 pages, 334 illustrations. Six 
folding plates. $3.00 

LOCOMOTIVE BREAKDOWNS AND THEIR REM- 
EDIES. By Geo. L. Fowler. Revised by Wm. W. Wood, 
Air-Brake Instructor. Just issued 19 10 Revised pocket edition. 
It is out of the question to try and tell you about every subject 
that is covered in this pocket edition of Locomotive Breakdowns. 
Just imagine all the common troubles that an engineer may ex- 
pect to happen some time, and then add all of the unexpected 
ones, troubles that could occur, but that you had never thought 
about, and you will find that they are all treated with the very 
best methods of repair. Walschaert Locomotive Valve Gear 
Troubles, Electric Headlight Troubles, as well as Questions and 
Answers on the Air Brake are all included. 294 pages. Fully 
illustrated. $1.00 

LOCOMOTIVE CATECHISM. By Robert Grimshaw. 
27th revised and enlarged edition. This may well be called an 
encyclopedia of the locomotive. Contains over 4,000 examina- 
tion questions with their answers, including among them those 
asked at the First, Second and Third year's Examinations. 
825 pages, 437 illustrations and 3 folding plates. $2.50 

13 



NEW YORK AIK-BHAKE CATECHISM. By Robert 

H. Blackall. This is a complete treatise on the New York 
Air-Brake and Air-Signalling Apparatus, giving a detailed de- 
scription of all the parts, their operation, troubles, and the 
methods of locating and remedying the same. 200 pages, fully- 
illustrated. $1.00 

POCKET-RAILROAD DICTIONARY AND VADE ME- 
CUM. _ By Fred H. Colvin, Associate Editor "American 
Machinist." _ Different from any book you ever saw. Gives clear 
and concise information on just the points you are interested in. 
It's really a pocket dictionary, fully illustrated, and so arranged 
that you can find just what you want in a second without an 
index. Whether you are interested in Axles or Acetylene; Com- 
pounds or Counter Balancing; Rails or Reducing Valves; Tires 
or Turntables, you'll find them in this little book. It's very 
complete. Flexible cloth cover, 200 pages. SI. 00 

TRAIN RULES AND DESPATCHING. By H. A. Dalby. 
Contains the standard code for both single and double track a.nd 
explains how trains are handled under all conditions. Gives all 
signals in colors, is illustrated wherever necessary, and the 
most complete book in print on this important subject. Bound 
in fine seal flexible leather. 221 pages. SI. 50 

WALSCHAERT LOCOMOTIVE VALVE GEAR. By 

Wm. W. Wood. If you would thoroughly understand the 
Walschaert Valve Gear, you should possess a copy of this book. 
The author divides the subject into four divisions, as follows: 
I. Analysis of the gear. II. Designing and erecting of the gear. 
III. Advantages of the gear. IV. Questions and answers re- 
lating to the Walschaert Valve Gear. This book is specially valu- 
able to those preparing for promotion. Nearly 200 pages. SI. 50 

WESTINOHOUSE E T AIR-BRAKE INSTRUCTION 
POCKET BOOK CATECHISM. By Wm. W. Wood, Air-Brake 
Instructor. A practical work containing examination questions 
and answers on the E T Equipment. Covering what the E T 
Brake is. How it should be operated. What to do when de- 
fective. Not a question can be asked of the engineman up for 
promotion on either the No. 5 or the No. 6 E T equipment that 
is not asked and answered in the book. If you want to thor- 
oughly understand the E T equipment get a copy of this book. 
It covers every detail. Makes Air-Brake troubles and examina- 
tions easy. Fully illustrated with colored plates, showing 
various pressures. $3.00 



MACHINE SHOP PRACTICE 



AMERICAN TOOL MAKING AND INTERCHANGE- 
ABLE MANUFACTURING. By J. V. Woodworth. A 
practical treatise on the designing, constructing, use, and in- 
stallation of tools, jigs, fixtures, devices, special appliances, 
sheet-metal working processes, automatic mechanisms, and 
labor-saving contrivances; together with their use in the lathe 
milling machine, turret lathe, screw machine, boring mill, power 
press, drill, subpress, drop hammer, etc., for the working of 
metals, the production of interchangeable machine parts, and 
the manufacture of repetition articles of metal. 560 pages, 
600 illustrations. $4.00 

14 



HENLEY'S ENCYCLOPEDIA OF PRACTICAL EN- 
GINEERING AND ALLIED TRADES. Edited by Joseph 
'G. Horner. A.M.I.Mech.I. This work covers the entire prac- 
tice of Civil and Mechanical Engineering. The best known ex- 
perts in all branches of engineering have contributed to these 
volumes. The Cyclopedia is admirably well adapted to the needs 
of the beginner and the self-taught practical man, as well as the 
mechanical engineer, designer, draftsman, shop superintendent, 
foreman and machinist. 

It is a modern treatise in five volumes. Handsomely bound 
in Half Morocco, each volume containing nearly 500 pages, with 
thousands of illustrations, including diagrammatic and sectional 
drawings with full explanatory details. 825.00 for the com- 
plete set of five volumes. 86.00 per volume, when ordered singly. 

MACHINE SHOP ARITHMETIC. By Colvin-Cheney. 
Most popular book for shop men. Shows how all shop problems 
are worked out and "why." Includes change gears for cutting 
any threads; drills, taps, shink and force fits; metric system 
of measurements and threads. Used by all classes of mechanics 
and for instruction of Y. M. C. A. and other schools. Fifth 
edition. 131 pages. 50 cents 

MECHANICAL MOVEMENTS, POWERS, AND DE- 
VICES. By Gardner D. Hiscox. This is a collection of 1890 
engravings of different mechanical motions and appliances, ac- 
companied by appropriate text, making it a book of great value 
to the inventor, the draftsman, and to all readers with mechanical 
tastes. The book is divided into eighteen sections or chapters 
in which the subject matter is classified under the following 
heads: Mechanical Powers, Transmission of Power, Measurement 
of Power, Steam Power, Air Power Appliances, Electric Powei 
and Construction, Navigation and Roads, Gearing, Motion and 
Devices, Controlling Motion, Horological, Mining, Mill ancj 
Factory Appliances, Construction and Devices, Drafting Devices, 
Miscellaneous Devices, etc. nth edition. 400 octavo pages. 

$2.50 

MECHANICAL APPLIANCES, MECHANICAL MOVE- 
MENTS AND NOVELTIES OF CONSTRUCTION. By 

Gardner D. Hiscox. This is a supplementary volume to the 
one upon mechanical movements. Unlike the first volume, 
which is more elementary in character, this volume contains 
illustrations and descriptions of many combinations of motions 
and of mechanical devices and appliances found in different lines 
of Machinery. Each device being shown by a line drawing with 
a description showing its working parts and the method of opera- 
tion. From the multitude of devices described, and illustrated, 
might be mentioned, in passing, such items as conveyors and 
elevators, Prony brakes, thermometers, various types of boilers, 
solar engines, oil-fuel burners, condensers, evaporators, Corliss 
and other valve gears, governors, gas engines, water motors of 
various descriptions, air ships, motors and dynamos, automobile 
and motor bicycles, railway block signals, car couples, link and 
gear motions, ball bearings, breech block mechanism for heavy 
guns, and a large accumulation of others of equal importance. 
1,000 specially made engravings. 396 octavo pages. 82.50 

SPECIAL OFFER These * wo volumes sell for $2. so each, 
f\M-. \j ci\ k ut when the two volumes are ordered 
-at one time from us, we send them prepaid to any address in the 
world, on receipt of $4.00. You save $1 by ordering the two 
volumes of Mechanical Movements at one time. 

tS 



MODERN MACHINE SHOP CONSTRUCTION, EQUIP- 
MENT AND MANAGEMENT. By Oscar E. Perrigo. 
The only work published that describes the Modern Machine 
Shop or Manufacturing Plant from the time the grass is growing 
on the site intended for it until the finished product is shipped. 
Just the book needed by those contemplating the erection of 
modern shop buildings, the rebuilding and reorganization of old 
ones, or the introduction of Modern Shop Methods, Time and 
Cost Systems. It is a book written and illustrated by a prac- 
tical shop man for practical shop men who are too busy to read 
theories and want facts. It is the most complete all-around book 
of its kind ever published. 400 ^rge quarto pages, 225 original 
and specially-made illustrations. $5.00 

MODERN MACHINE SHOP TOOLS; THEIR CON- 
STRUCTION, OPERATION, AND MANIPULATION. By 

W. H. Vandervoort. A work of 555 pages and 673 illustra- 
tions, describing in every detail the construction, operation, and 
manipulation of both Hand and Machine Tools. Includes 
chapters on filing, fitting, and scraping surfaces; on drills, ream- 
ers, taps, and dies; the lathe and its tools; planers, shapers, 
and their tools; milling machines and cutters; gear cutters and 
gear cutting; drilling machines and drill work; grinding ma- 
chines and their work; hardening and tempering; gearing, 
belting and transmission machinery; useful data and tables. 

$4.00 

THE MODERN MACHINIST. By John T. Usher. This 
book might be called a compendium of shop methods, showing a 
variety of special tools and appliances which will give new ideas 
to many mechanics from the superintendent down to the man 
at the bench. It will be found a valuable addition to any machin- 
ist's library and should be consulted whenever a new or difficult 
job is to be done, whether it is boring, milling, turning, or plan- 
ing, as they are all treated in a practical manner. Fifth edition. 
320 pages, 250 illustrations. $2.50 

MODERN MECHANISM. Edited by Park Benjamin. A 
practical treatise on machines, motors and the transmissien of 
power, being a complete work and a supplementary volume to 
Appleton's Cyclopedia of Applied Mechanics. Deals solely with 
the principal and most useful advances of the past few years. 
959 pages containing over 1,000 illustrations; bound in half 
morocco. $4.00 

MODERN MILLING MACHINES: THEIR DESIGN, 
CONSTRUCTION AND OPERATION. By Joseph G. 
Horner. This book describes and illustrates the Milling Ma- 
chine and its work in such a plain, clear, and forceful manner, 
and illustrates the subject so clearly and completely, that the 
up-to-date machinist, student, or mechanical engineer can not 
afford to do without the valuable information which it contains. 
It describes not only the early machines of this class, but notes 
their gradual development into the splendid machines of the 
present day, giving the design and construction of the various 
types, forms, and special features produced by prominent 
manufacturers, American and foreign. 304 pages, 300 illustra- 
tions. $4.00 

" SHOP KINKS." By 3!obert Grimshaw. This shows 
special methods of doing work of various kinds, and reducing 
cost of production. Has hints and kinks from some of the largest 
shops in this country and Europe. You are almost sure to find 
some that apply to your work, and in such a way as to save time 
and trouble. 400 pages. Fourth edition. $2.60 

16 



TOOLS FOR MACHINISTS AND WOOD WORKERS, 
INCLUDING INSTRUMENTS OF MEASUREMENT. By 

Joseph G. Horner. A practical treatise of 340 pages, fully 
illustrated and comprising a general description and classifica- 
tion of cutting tools and tool angles, allied cutting tools for 
machinists and woodworkers; shearing tools; scraping tools; 
saws; milling cutters; drilling and boring tools; taps and dies; 
punches and hammers; and the hardening, tempering and 
grinding of these tools. Tools for measuring and testing work, 
including standards of measurement; surface plates; levels; 
surface gauges; dividers; calipers; verniers; micrometers; 
snap, cylindrical and limit gauges; screw thread, wire and 
reference gauges, indicators, templets, etc. $3.50 

MANUAL TRAINING 



ECONOMICS OF MANUAL TRAINING. By T -ouis 
Rouillion. The only book that gives just the information 
needed by all interested in manual training, regarding buildings, 
equipment and supplies. Shows exactly what is needed for all 
grades of the woi x from the Kindergarten to the High and Nor- 
mal School. Gives itemized lists of everything needed and tells 
just what it ought to cost. Also shows where to buy supplies. 

SI. 50 

MARINE ENGINEERING 



MARINE ENGINES AND BOILERS, THEIR DESIGN 
AND CONSTRUCTION. By Dr. G. Bauer, Leslie S. 
Robertson, and S. Bryan Donkin. This work is clearly 
written, thoroughly systematic, theoretically sound; while the 
character of its plans, drawings, tables, and statistics is without 
reproach. The illustrations are careful reproductions from 
actual working drawings, with some well-executed photographic 
views of completed engines and boilers. 89.00 net 

MINING 



'ORE DEPOSITS OF SOUTH AFRICA WITH A 
CHAPTER ON HINTS TO PROSPECTORS. By J. P. John- 
son. This book gives a condensed account of the ore-deposits 
at present known in South Africa. It is also intended as a guide 
to the prospector. Only an elementary knowledge of geology 
and some mining experience are necessary in order to under- 
stand this work. With these qualifications, it will materially 
assist one in his search for metalliferous mineral occurrences 
and, so far as simple ores are concerned, should enable one to 
form some idea of the possibilities of any they may find. 

Among the chapters given are: Titaniferous and Chromif- 
erous Iron Oxides — Nickel — Copper — Cobalt — Tin — Molyb- 
denum — Tungsten — Lead — Mercury — Antimony — I r o n — Hints 
to Prospectors. Illustrated. 82.00 

PRACTICAL COAL MINING. By T. H. Cockin. An im- 
portant work, containing 428 pages and 213 illustrations, com- 
plete with practical details, which will intuitively impart to the 
reader, not only a general knowledge of the principles of coal 
mining, but also considerable insight into allied subjects. The 
treatise is positively up to date in every instance, and should 
be in the hands of every colliery engineer, geologist, mine 
operator, superintendent, foreman, and all others who are in- 
terested in or connected with the industry. 82.50 

17 



PHYSICSAND CHEMISTRY OF MINING. By T. H, 

Byrom. A practical work for the use of all preparing for ex- 
aminations in mining or qualifying for colliery managers' cer- 
tificates. The aim of the author in this excellent book is to place 
clearly before the reader useful and authoritative data which 
will render him valuable assistance in his studies. The only work 
of its kind published. The information incorporated in it will 
prove of the greatest practical utility to students, mining en- 
gineers, colliery managers, and all others who are specially in- 
terested in the present- day treatment of mining problems. 160 
pages. Illustrated. $2.00 

MISCELLANEOUS 



BRONZES. Henley's Twentieth Century Receipt Book con- 
tains many practical formulas on bronze casting, imitation 
bronze, bronze polishes, renovation of bronze. See page 24 for 
full description of this book. $3.00 

EMINENT ENGINEERS. By Dwight Goddard. Every- 
one who appreciates the effect of such great inventions as the 
Steam Engine, Steamboat, Locomotive, Sewing Machine, Steel 
Working, and other fundamental discoveries, is interested in 
knowing a little about the men who made them and their achieve- 
ments. 

Mr. Goddard has selected thirty-two of the world's engineers 
who have contributed most largely to the advancement of our 
civilization by mechanical means, giving only such facts as are of 
general interest and in a way which appeals to all, whether 
mechanics or not. 280 pages, 35 illustrations. $1.50 

LAWS OF BUSINESS, By Theophilus Parsons, LL.D. 
The Best Book for Business Men ever Published. Treats clearly 
of Contracts, Sales, Notes, Bills of Exchange, Agency, Agree- 
ment, Stoppage in Transitu, Consideration, Limitations, Leases, 
Partnership, Executors, Interest, Hotel Keepers, Fire and Life 
Insurance, Collections, Bonds, Frauds, Receipts, Patents, Deeds 
Mortgages, Liens, Assignments, Minors, Married Women, Arbi- 
tration, Guardians, Wills, etc. Three Hundred Approved Forms 
are given. Every Business Man should have a copy of this book 
for ready reference. The book is bound in full sheep, and Con- 
tains 864 Octavo Pages. Our special price. $3.50 

PATTERN MAKING 

PRACTICAL PATTERN MAKING. By F. W. Barrows. 

This is a very complete and entirely practical treatise on the 
subject of oattern making, illustrating pattern work in wood and 
metal. From its pages you are taught just what you should 
know about pattern making. It contains a detailed description 
of the materials used by pattern makers, also the tools, both 
those for hand use, and the more interesting machine tools; hav- 
ing complete chapters on The Band Saw, The Buzz Saw, and The 
Lathe. Individual patterns of many different kinds are fully 
illustrated and described, and the mounting of metal patterns on 
plates for molding machines is included. $3.00 

PERFUMERY 



HENLEY'S TWENTIETH CENTURY BOOK OF RE- 
CEIPTS, FORMULAS AND PROCESSES. Edited by G. D. 
Hiscox. The most valuable Techno-Chemical Receipt Book 
published. Contains over 10,000 practical Receipts many of 
which will prove of special value to the perfumer, a mine of in- 
formation, up to date in every respect. Cloth, $3.00; half 
morocco. See page 24 for full description of this book. $4.00 

18 



PERFUMES AND THEIR PREPARATION. By G. W. 

Askinson, Perfumer. A comprehensive treatise, in which 
there has been nothing omitted that could be of value to the 
Perfumer. Complete directions for making handkerchief per- 
fumes, smelling-salts, sachets, fumigating pastilles; preparations 
for the care of the skin, the mouth, the hair, cosmetics, hair dyes 
and other toilet articles are given, also a detailed description 
of aromatic substances; their nature, tests of purity, and 
wholesale manufacture. A book of general, as well as profes- 
sional interest, meeting the wants not only of the druggist and 
perfume manufacturer, but also of the general public. Third 
edition. 312 pages. Illustrated. 83.00 



PLUMBING 



MODERN PLUMBING ILLUSTRATED. By R. M. 

Starbuck. The author of this book, Mr. R. M. Starbuck, is one 
of the leading authorities on plumbing in the United States. The 
book represents the highest standard of plumbing work. It has 
been adopted and used as a reference book by the United States 
Government, in its sanitary work in Cuba, Porto Rico and the 
Philippines, and by the principal Boards of Health of the United 
States and Canada. 

It gives Connections, Sizes and Working Data for All Fixtures 
and Groups of Fixtures. It is helpful to the Master Plumber in 
Demonstrating to his customers and in figuring work. It gives 
the Mechanic and Student quick and easy Access to the best 
Modern Plumbing Practice. Suggestions for Estimating Plumb- 
ing Construction are contained in its pages. This book repre- 
sents, in a word, the latest and best up-to-date practice, and 
should be in the hands of every architect, sanitary engineer 
and plumber who wishes to keep himself up to the minute on this 
important feature of construction. 400 octavo pages, fully 
illustrated by 55 full- page engravings. $4.00 



RUBBER 



HENLEY'S TWENTIETH CENTURY BOOK OF RE- 
CEIPTS, FORMULAS AND PROCESSES. Edited by Gard- 
ner D. Hiscox. Contains upward of 10,000 practical receipts, 
including among them formulas on artificial rubber. See page 
24 for full description of this book. $3.00 

RUBBER HAND STAMPS AND THE MANIPULATION 
OF INDIA RUBBER. By T. O'Conor Sloane. This book 
gives full details on all points, treating in a concise and simple 
manner the elements of nearly everything it is necessary to under- 
stand for a commencement in any branch of the India Rubber 
Manufacture. The making of all kinds of Rubber Hand Stamps, 
Small Articles of India Rubber, U. S. Government Composi- 
tion, Dating Hand Stamps, the Manipulation of Sheet Rubber, 
Toy Balloons, India Rubber Solutions, Cements, Blackings, 
Renovating Varnish, and Treatment for India Rubber Shoes, 
etc.; the Hektograph Stamp Inks, and Miscellaneous Notes, 
with a Short Account of the Discovery, Collection, and Manufac- 
ture of India Rubber are set forth in a manner designed to be 
readily understood, the explanations being plain and simple. 
Second edition. 144 cages. Illustrated. $1.00 

10 



SAWS 

SAW FILING AND MANAGEMENT OF SAWS. By 

Robert Grimshaw. A practical hand book on filing, gumming, 
swaging, hammering, and the brazing of band saws, the speed, 
work, and power to run circular saws, etc. A handy book for 
those who have charge of saws, or for those mechanics who do 
their own filing, as it deals with the proper shape and pitches of 
saw teeth of all kinds and gives many useful hints and rules for 
gumming, setting, and filing, and is a practical aid to those who 
use saws for any purpose. New edition, revised and enlarged. 
Illustrated. $1.00 

SCREW CUTTING 



THREADS AND THREAD CUTTING. By Colvin and 
Stabel. This clears up many of the mysteries of thread- 
cutting, such as double and triple threads, internal threads, catch- 
ing threads, use of hobs, etc. Contains a lot of useful hints and 
several tables. 25 cents 

SHEET METAL WORK 



DIES, THEIR CONSTRUCTION AND USE FOR THE 
MODERN WORKING OF SHEET METALS. By J. V. 

Woodworth. A new book by a practical man, for those who 
wish to know the latest practice in the working of sheet metals. 
It shows how dies are designed, made and used, and those who 
are engaged in this line of work can secure many valuable 
suggestions. $3.00 

PUNCHES, DIES AND TOOLS FOR MANUFACTUR- 
ING IN PRESSES. By J. V. Woodworth. A work of 500 
pages and illustrated by nearly 700 engravings, being an en- 
cyclopedia of die-making, punch-making, die sinking, sheet- 
metal working, and making of special tools, subpresses, devices 
and mechanical combinations for punching, cutting, bending, 
forming, piercing, drawing, compressing, and assembling sheet- 
metal parts and also articles of other materials in machine tools. 

$4.00 

STEAM ENGINEERING 

AMERICAN STATIONARY ENGINEERING. By W. 

E. Crane. A new book by a well-known author. Begins at 
the boiler room and takes in the whole power plant. Contains 
the result of years of practical experience in all sorts of engine 
rooms and gives exact information that cannot be found else- 
where. It's plain enough for practical men and yet of value to 
those high in the profession. Has a complete examination for a 
license. $2.00 

BOILER ROOM CHART. By Geo. L. Fowler. A Chart 
— size 14x28 inches — showing in isometric perspective the 
mechanisms belonging in a modern boiler room. Water tube 
boilers, ordinary grates and mechanical stokers, feed water 
heaters and pumps comprise the equipment. The various parts 
are shown broken or removed, so that the internal construction 
is fully illustrated. Each part is given a reference number, and 
these, with the corresponding name, are given in a glossary 
printed at the sides. This chart is really a dictionary of the 
boiler room — the names of more than 200 parts being given. 
It is educational — worth many times its cost. 25 cents 

20 



ENGINE RUNNER'S CATECHISM. By Robert Grim- 
Shaw. Tells how to erect, adjust, and run the principal steam 
engines in use in the United States. The work is of a handy- 
size for the pocket. To young engineers this catechism will be 
of great value, especially to those who may be preparing to go 
forward to be examined for certificates of competency; and 
to engineers generally it will be of no little service as they will 
find in this volume more really practical and useful information 
than is to be found anywhere else within a like compass. 387 
pages. Sixth edition. 82.00 

ENGINE TESTS AND BOILER EFFICIENCIES. By 

J. Buchetti. This work fully describes and illustrates the 
method of testing the power of steam engines, turbine and 
explosive motors. The properties of steam and the evapora- 
tive power of fuels. Combustion of fuel and chimney draft; 
with formulas explained or practically computed. 255 pages, 
179 illustrations. 83.00 

HORSE POWER CHART. Shows the horse power of any 
stationary engine without calculation. No matter what the 
cylinder diameter or stroke; the steam pressure or cut-off; the 
revolutions, or whether condensing or non-condensing, it's all 
there. Easy to use, accurate, and saves time and calculations. 
Especially useful to engineers and designers. 50 cents 

MODERN STEAM ENGINEERING IN THEORY AND 
PRACTICE. By Gardner D. Hiscox. This is a complete and 
practical work issued for Stationary Engineers and Firemen 
dealing with the care and management of Boilers, Engines, 
Pumps, Superheated Steam, Refrigerating Machinery, Dyna- 
mos, Motors, Elevators, Air Compressors, and all other branches 
with which the modern Engineer must be familiar. Nearly 
200 Questions with their Answers on Steam and Electrical 
Engineering, likely to be asked by the Examining Board, are 
included. 487 pages, 405 engravings. 83.00 

STEAM ENGINE CATECHISM. By Robert Grimshaw. 
This volume of 413 pages is not only a catechism on the question 
and answer principle; but it contains formulas and worked-out 
answers for all the Steam problems that appertain to the opera- 
tion and management of the Steam Engine. Illustrations of 
various valves and valve gear with their principles of operation 
are given. 34 tables that are indispensable to every engineer and 
fireman that wishes to be progressive and is ambitious to become 
master of his calling are within its pages. It is a most valuable 
instructor in the service of Steam Engineering. Leading en- 
gineers have recommended it as a valuable educator for the be- 
ginner as well as a reference book for the engineer. Sixteenth 
edition. 82.0€ 

STEAM ENGINEER'S ARITHMETIC. By Colvin- 
Cheney. A practical pocket book for the Steam Engineer. 
Shows how to work the problems of the engine room and shows 
"why." Tells how to figure horse-power of engines and boilers; 
area of boilers; has tables of areas and circumferences; steam 
tables; has a dictionary of engineering terms. Puts you onto 
all of the little kinks in figuring whatever there is to figure 
around a power plant. Tells you about the heat unit; absolute 
zero; adiabatic expansion; duty of engines; factor of safety; 
and 1,001 other things; and everything is plain and simple — 
not the hardest way to figure, but the easiest. 50 ceuts 



STEAM HEATING AND VENTILATION 

PRACTICAL, STEAM, HOT-WATER HEATING AND 
VENTILATION. By A. G. King. This book is the standard 
and latest work published on the subject and has been prepared 
for the use of all engaged in the business of steam, hot-water 
heating and ventilation. It is an original and exhaustive work. 
Tells how to get heating contracts, how to install heating and 
ventilating apparatus, the best business methods to be used, with 
"Tricks of the Trade" for shop use. Rules and data for esti- 
mating radiation and cost and such tables and information as 
make it an indispensable work for everyone interested in steam, 
hot -water heating and ventilation. It describes all the principal 
systems of steam, hot-water, vacuum, vapor and vacuum- 
vapor heating, together with the new accelerated systems of 
hot-water circulation, including chapters on up-to-date methods 
of ventilation and the fan or blower system of heating and venti- 
lation. 

You should secure a copy of this book, as each chapter con- 
tains a mine of practical information. 367 pages, 300 detailed 
engravings. $3.00 

STEAM PIPES 



STEAM PIPES: THEIR DESIGN AND CONSTRUC- 
TION. By Wm. H. Booth. The work is well illustrated in regard 
to pipe joints, expansion offsets, flexible joints, and self-contained 
sliding joints for taking up the expansion of long pipes. In fact, 
the chapters on the flow of Steam and expansion of pipes are most 
valuable to all steam fitters and users. The pressure strength of 
pipes and method of hanging them is well treated and illustrated. 
Valves and by-passes are fully illustrated and described, as are 
also flange joints and their proper proportions. Exhaust heads 
and separators. One of the most valuable chapters is that on 
superheated steam and the saving of steam by insulation with 
the various kinds of felting and other materials, with comparison 
tables of the loss of heat in thermal units from naked and felted 
steam pipes. Contains 187 pages. 82.00 

STEEL 



AMERICAN STEEL WORKER. By E. R. Markham. 
The standard work on hardening, tempering and annealing steel 
of all kinds. A practical book for the machinist, tool maker or 
superintendent. Shows just how to secure best results in any 
case that comes along. How to make and use furnaces and case 
harden; how to handle high-speed steel and how to temper for all 
classes of work. $2.50 

HARDENING, TEMPERING, ANNEALING, AND 
FORGING OF STEEL. By J. V. Woodworth. A new book 
containing special directions for the successful hardening and 
tempering of all steel tools. Milling cutters, taps, thread dies, 
reamers, both solid and shell, hollow mills, punches and dies, 
and all kinds of sheet-metal working tools, shear blades, saws, 
fine cutlery and metal-cutting tools of all descriptions, as well 
as for all implements of steel both large and small, the simplest, 
and most satisfactory hardening and tempering processes are 
presented. The uses to which the leading brands of steel may be 
adapted are concisely presented, and their treatment for work- 
ing under different conditions explained, as are also the special 
methods for the hardening and tempering of special brands. 
320 pages, 250 illustrations. 82.50 

22 



HENLEY'S TWENTIETH CENTURY BOOK OF RE- 
CEIPTS, FORMULAS AND PROCESSES. Edited by Gard- 
ner D. Hiscox. The most valuable techno-chemical Receipt 
book published, giving, among other practical receipts, methods 
of annealing, coloring, tempering, welding, plating, polishing 
and cleaning steel. See page 24 for full description of this book. 

$3.00 

WATCH MAKING 



HENLEY'S TWENTIETH CENTURY BOOK OF RE- 
CEIPTS, FORMULAS AND PROCESSES. Edited by 
Gardner D. Hiscox. Contains upwards of 10,000 practical 
formulas including many watchmakers' formulas. 83. OO 

WATCHMAKER'S HANDBOOK. By Claudius Saunier. 
No work issued can compare with this book for clearness and 
completeness. It contains 498 pages and is intended as a work- 
shop companion for those engaged in Watchmaking and allied 
Mechanical Arts. Nearly 250 engravings and fourteen plates 
are included. 83.00 

WIRELESS TELEPHONES 



WIRELESS TELEPHONES AND HOW THEY WORK. 

By James Erskine-Murray. This work is free from elaborate 
details and aims at giving a clear survey of the way in which 
Wireless Telephones work. It is intended for amateur workers 
and for those whose knowledge of Electricity is slight. Chap- 
ters contained: How We Hear — Historical — The Conversion of 
Sound into Electric Waves — Wireless Transmission — The Pro- 
duction of Alternating Currents of High Frequency — How the 
Electric Waves are Radiated and Received — The Receiving 
Instruments — Detectors — Achievements and Expectations — 
Glossary of Technical Words. Cloth. 81.00 



93 




Henley's Twentieth Century 

Book of 

Recipes, Formulas 
and Processes 

W& Edited by GARDNER D. HISCOX, M.E. 
Price $3.00 Cloth Binding $4.00 Half Morocco Binding 

Contains ove rJjQ^ OOOjelec^Scientif^ 

Technologi cal^ndjracUcal^cipes^and 

Processes, includin g Hundreds_of 

So-Cal led Trade Secrets 

for Every Business 

THIS book of 800 pages is the most complete Book of 
Recipes ever published, giving thousands of recipes 
for the manufacture of valuable articles for every -day 
use. Hints, Helps, Practical Ideas and Secret Processes 
are revealed within its pages. It covers every branch of 
the useful arts and tells thousands of ways of making 
money and is just the book everyone should have at his 

command. - , 

The pages are filled with matters of intense interest and 
immeasurable practical value to the Photographer, the 
Perfumer, the Painter, the Manufacturer of Glues, Pastes, 
Cements and Mucilages, the Physician, the Druggist, the 
Electrician, the Brewer, the Engineer, the Foundryman, 
the Machinist, the Potter, the Tanner, the Confectioner, 
the Chirooodist, the Manufacturer of Chemical Novelties 
and Toilet Preparations, the Dyer, the Electroplater, 
the Enameler, the Engraver, the Provisioner, the Glass 
Worker, the Goldbeater, the Watchmaker and Jeweler, 
the Ink Manufacturer, the Optician, the Farmer, the Dairy- 
man, the Paper Maker, the Metal Worker, the Soap Maker, 
the Veterinary Surgeon, and the Technologist in general. 
A book to which you may turn with confidence that you 
will find what you are looking for. A mine of informa- 
tion up-to-date in every respect. Contains an immense 
number of formulas that every one ought to have that are 
not found in any other work. 



JUK 8 1912 



018 373 759 4 * 



